Are you tired of painful intramuscular injections and wondering if there's a more comfortable way to administer your testosterone replacement therapy?
For decades, intramuscular (IM) injections have been the standard method for testosterone delivery, requiring long needles, deeper tissue penetration, and often resulting in discomfort and injection site reactions. However, a growing body of clinical evidence demonstrates that subcutaneous (SubQ) testosterone injections offer a safe, effective, and often preferred alternative for men on testosterone replacement therapy (TRT).
This comprehensive guide examines the science, clinical data, and practical considerations of subcutaneous testosterone administration. You'll learn about the pharmacokinetic advantages, reduced side effect profile, patient satisfaction data, and proper injection techniques that make SubQ testosterone an increasingly popular choice among TRT patients and clinicians. Whether you're considering switching from IM injections or starting TRT for the first time, understanding subcutaneous delivery can help you make informed decisions about your hormone optimization protocol.
Subcutaneous injections deliver testosterone into the fatty tissue layer just beneath the skin (the hypodermis), rather than deep into muscle tissue as with intramuscular injections. This superficial administration uses shorter, thinner needles—typically insulin syringes with 27-31 gauge needles that are 1/2 inch or less in length—making the injection process significantly more comfortable and easier to self-administer.
The subcutaneous space has different absorption characteristics compared to muscle tissue. While muscle tissue has rich blood supply allowing for rapid absorption, subcutaneous fat tissue provides slower, more sustained release of testosterone. This pharmacokinetic difference translates to more stable testosterone levels with reduced peak-to-trough fluctuations—a critical advantage for many men seeking consistent hormone levels throughout their dosing interval.
Common subcutaneous injection sites include the abdomen (avoiding the area around the belly button), the front and outer portions of the thighs, and the back of the upper arms. These sites offer adequate subcutaneous tissue for injection while being easily accessible for self-administration. Rotating injection sites is essential to prevent tissue irritation and maintain the integrity of the subcutaneous tissue over time.
Historical Context and FDA Approval
While testosterone therapy has been available since the 1930s, subcutaneous administration has only gained widespread clinical attention in the past two decades. The FDA approval of Xyosted (testosterone enanthate subcutaneous injection) in 2018 marked a significant milestone, providing the first FDA-approved subcutaneous testosterone product specifically designed for hypogonadism treatment.
Xyosted uses an autoinjector system delivering 50 mg, 75 mg, or 100 mg of testosterone enanthate weekly. Pharmacokinetic studies demonstrate that this subcutaneous formulation produces steady serum testosterone concentrations with median peak levels occurring approximately 12 hours post-dose, followed by a slow decline over the dosing interval. However, many clinicians and patients have also successfully adapted traditional testosterone cypionate and enanthate—originally formulated for intramuscular use—for subcutaneous administration using standard insulin syringes.
Multiple clinical studies have established that subcutaneous testosterone administration achieves therapeutic testosterone levels comparable to intramuscular injections. A landmark 2017 study published in the Journal of Clinical Endocrinology & Metabolism evaluated 63 transgender men receiving weekly subcutaneous testosterone cypionate or enanthate at doses of 50-150 mg. The study found that both total and free testosterone concentrations were consistently maintained within the normal adult male range, with efficacy demonstrated across a wide range of body mass index values (19.0 to 49.9 kg/m²).
A 2024 pilot study comparing pharmacokinetics and patient acceptability of subcutaneous versus intramuscular testosterone found that SubQ administration resulted in similar testosterone exposure while offering improved patient satisfaction. Importantly, the research demonstrated that subcutaneous injection produces more stable testosterone levels with reduced peak-to-trough fluctuations compared to the supraphysiological peaks often seen with intramuscular administration.
The median weekly dose for subcutaneous administration typically ranges from 50-100 mg, which is often lower than the traditional 100-200 mg doses used for biweekly intramuscular injections. This dose reduction is possible due to improved bioavailability and more consistent absorption from subcutaneous tissue. Studies indicate that therapeutic serum testosterone concentrations can be maintained with approximately 75% of the typical intramuscular dose when administered subcutaneously on a weekly basis.
Pharmacokinetic Advantages
The pharmacokinetic profile of subcutaneous testosterone differs meaningfully from intramuscular administration. Research demonstrates that subcutaneous injection of testosterone enanthate produces a slower time to peak concentration (approximately 8.0 days for SubQ versus 3.3 days for IM), while maintaining similar overall testosterone exposure. This slower, more sustained release pattern results in more physiologic testosterone levels that better mimic endogenous production.
Short-acting intramuscular testosterone formulations (cypionate and enanthate) are associated with rapid increases in serum testosterone, often reaching supraphysiological levels within days of injection, followed by a return to baseline by 10-14 days and potential decline to subphysiological levels by 3 weeks if not re-dosed. These dramatic fluctuations can contribute to mood swings, energy variations, and increased side effects. In contrast, subcutaneous administration provides more consistent testosterone levels throughout the dosing interval, potentially reducing these cyclical symptoms.
Studies examining dihydrotestosterone (DHT) and estradiol levels after subcutaneous injection find that these testosterone metabolites increase in a similar manner regardless of administration route. Importantly, subcutaneous testosterone enanthate maintains stable DHT and estradiol concentrations with minimal fluctuations, suggesting that the conversion of testosterone to its metabolites occurs consistently throughout the dosing period.
One of the most compelling advantages of subcutaneous testosterone administration is the significantly reduced risk of erythrocytosis (elevated hematocrit). Erythrocytosis is one of the most common adverse effects of testosterone therapy, with rates ranging from 5-66% in men receiving intramuscular testosterone—the wide range reflecting differences in dosing, frequency, and patient populations across studies.
A 2022 retrospective study specifically evaluated erythrocytosis rates in 94 cisgender men receiving subcutaneous testosterone cypionate. The study found that 32% of men developed new-onset erythrocytosis (hematocrit ≥53%), which represents a substantial reduction compared to the 40-66% rates commonly reported with intramuscular administration. This clinically meaningful difference suggests that the route of administration significantly influences red blood cell production independent of testosterone dose or exposure.
A comprehensive 2024 study examining erythrocytosis in transgender patients found that intramuscular testosterone was associated with significantly higher hematocrit levels compared to transdermal formulations, even after controlling for testosterone levels. While the subcutaneous group was too small for statistical comparison in this study, the pattern suggested that route of administration plays an independent role in hematocrit elevation beyond simply the amount of testosterone delivered.
The mechanism underlying this reduced erythrocytosis risk likely relates to the more stable testosterone levels achieved with subcutaneous administration. Supraphysiological testosterone peaks—common with intramuscular injections—may trigger more aggressive erythropoietin stimulation and hepcidin suppression, leading to increased red blood cell production. By avoiding these peaks, subcutaneous administration may provide a safer erythropoietic profile while maintaining therapeutic testosterone exposure.
Injection Site Reactions and Tolerability
Subcutaneous testosterone administration is generally well-tolerated with minimal local adverse effects. In the 2017 transgender study of 63 patients receiving subcutaneous testosterone for up to 43 months, only 9 participants (14%) reported injection site reactions. These included minor, self-limited events such as small painless nodules that resolved within 2 days, transient urticaria lasting up to 3 days, mild local inflammation, and one case of self-limited cellulitis.
Notably, these reaction rates are considerably lower than those commonly reported with intramuscular injections, which frequently cause pain, bruising, and muscle soreness at injection sites. The smaller needle gauge, shorter needle length, and superficial injection technique all contribute to improved tolerability. Proper injection technique, site rotation, and appropriate needle selection further minimize the risk of local reactions.
Patient satisfaction data consistently demonstrates a strong preference for subcutaneous over intramuscular testosterone administration. In the 2017 Journal of Clinical Endocrinology & Metabolism study, 22 patients who had previously been receiving intramuscular testosterone were switched to subcutaneous administration. Among these patients, 20 (91%) expressed a marked preference for subcutaneous injections, while 2 (9%) reported a mild preference, and notably, zero patients preferred returning to intramuscular injections.
The reasons for this overwhelming preference are multifaceted. Subcutaneous injections involve less pain during administration, require smaller and shorter needles, are easier to self-administer without assistance, offer more convenient injection sites that patients can reach themselves, and produce fewer injection site reactions such as bruising or soreness. These practical advantages translate to improved treatment adherence—a critical factor in achieving optimal therapeutic outcomes with long-term testosterone therapy.
A 2023 prospective comparison study of subcutaneous versus intramuscular testosterone in transgender adolescents found that both methods were equally effective in achieving target testosterone levels and producing desired masculinizing effects. However, the subcutaneous group reported higher satisfaction scores, with particular emphasis on the reduced discomfort and increased autonomy in self-administration. This finding suggests that the preference for subcutaneous administration extends across different age groups and patient populations.
Improved Treatment Adherence
The ease of self-administration with subcutaneous injections has important implications for treatment adherence. Traditional intramuscular injections—particularly into the gluteal muscles—often require assistance from healthcare providers or family members, necessitating frequent clinic visits or complicated arrangements. This dependence can create significant barriers to consistent therapy.
Subcutaneous administration eliminates many of these barriers. The accessible injection sites (abdomen, thighs, upper arms), smaller needles, and simpler technique allow most patients to confidently self-inject after brief training. This autonomy not only improves convenience but also empowers patients to maintain consistent dosing schedules, leading to better therapeutic outcomes. Studies suggest that the improved adherence associated with subcutaneous testosterone may contribute to its favorable safety profile and patient satisfaction.
Clinical experience and published research suggest that weekly subcutaneous testosterone dosing of 50-100 mg effectively maintains therapeutic testosterone levels in most men. The FDA-approved Xyosted product uses a starting dose of 75 mg weekly, with dose adjustments based on trough testosterone concentrations measured after 6 weeks of treatment. For patients using compounded testosterone cypionate or enanthate for subcutaneous administration, a typical starting dose is 50-75 mg weekly.
Some clinicians and patients have adopted more frequent dosing schedules—including twice-weekly or even daily microdosing protocols—to further stabilize testosterone levels. Daily microdosing typically involves subcutaneous injections of 10-20 mg using insulin syringes. Advocates of this approach report benefits including even more stable testosterone levels, reduced estradiol fluctuations, and potentially lower aromatase activity. However, daily injections require greater commitment and may not be necessary or preferred by all patients.
Dosing should always be individualized based on patient response, symptom improvement, and laboratory monitoring. Factors influencing optimal dose include body weight, metabolism, SHBG levels, injection frequency, and individual treatment goals. Regular monitoring of total testosterone, free testosterone, estradiol, and hematocrit allows for appropriate dose adjustments to maintain target levels while minimizing side effects.
Proper Injection Technique
Correct subcutaneous injection technique is essential for maximizing comfort, efficacy, and safety. The recommended approach involves the following steps:
Site Selection and Preparation: Choose an appropriate injection site—abdomen (avoiding 2 inches around the belly button), front/outer thigh, or back of upper arm. Clean the area with an alcohol wipe and allow it to air dry completely. Gather supplies including testosterone vial, insulin syringe (typically 27-31 gauge, 1/2 inch or shorter), alcohol wipes, and a sharps container.
Drawing Up Medication: Draw air into the syringe equal to your dose. Insert the needle into the testosterone vial and inject the air. Invert the vial and slowly draw up the prescribed dose. Remove air bubbles by tapping the syringe and gently pushing the plunger until a small amount of testosterone appears at the needle tip.
Injection Procedure: Pinch the skin at the injection site to create a fold of fatty tissue. Insert the needle at a 45-90 degree angle (90 degrees is typically used with shorter needles). Inject slowly and steadily—rushing can increase the risk of lumps or irritation. Remove the needle quickly and apply gentle pressure with a clean cotton ball or gauze.
Site Rotation: Consistently rotate injection sites to prevent tissue damage and lipohypertrophy (lumps of fatty tissue buildup). Keep a simple injection log noting the date, location, and any reactions. This helps ensure systematic rotation and identifies any problematic sites.
Safety Considerations: Never reuse needles or syringes. Dispose of all sharps in an approved sharps container. If you experience warmth, redness, increasing pain, or signs of infection at an injection site, contact your healthcare provider. Small, temporary lumps or minor bruising are common and usually resolve within a few days.
Equipment and Supplies
For subcutaneous testosterone administration, patients typically use insulin syringes, which combine the needle and syringe in a single unit. Common specifications include:
Needle Gauge: 27-31 gauge needles are standard. Higher gauge numbers indicate thinner needles, which cause less discomfort. For testosterone oils, 27-29 gauge generally provides an optimal balance between comfort and ease of drawing up the medication.
Needle Length: 1/2 inch (12.7mm) or 5/16 inch (8mm) needles are most common. Shorter needles work well for most patients, though individuals with very low body fat may need 1/2 inch, while those with higher body fat can use shorter options.
Syringe Volume: 0.5 mL or 1 mL insulin syringes are typically adequate for weekly doses of 50-100 mg. For microdosing protocols with smaller daily doses, 0.3 mL syringes may be more convenient and allow for more precise measurement.
Note: Percentages and ranges represent compiled data from multiple clinical studies. Individual results may vary based on dose, frequency, patient characteristics, and other factors.
Men currently on intramuscular testosterone who wish to transition to subcutaneous administration should work with their healthcare provider to adjust dosing appropriately. A common approach involves reducing the total weekly testosterone dose by approximately 25-30% when switching from IM to SubQ, then adjusting based on follow-up laboratory testing.
For example, a patient on 200 mg intramuscular testosterone every two weeks (100 mg per week average) might transition to 75 mg subcutaneous weekly. Initial follow-up testing at 4-6 weeks allows for dose optimization based on trough testosterone levels, symptom response, and side effect profile. Most patients find that the more stable testosterone levels with subcutaneous administration require less frequent dose adjustments once optimal dosing is established.
During the transition period, patients should monitor for changes in energy, mood, libido, and other testosterone-dependent symptoms. Some men report improved symptom stability with the elimination of the peak-trough cycling associated with less frequent intramuscular injections. However, the transition should be gradual, and patience is necessary as it may take 6-8 weeks to reach stable testosterone levels with a new protocol.
Managing Elevated Hematocrit
For men who have developed erythrocytosis on intramuscular testosterone, transitioning to subcutaneous administration may help reduce hematocrit levels. The clinical evidence demonstrating lower erythrocytosis rates with SubQ testosterone makes this an attractive option for patients who have had to interrupt or discontinue therapy due to elevated hematocrit.
A typical management strategy involves switching to subcutaneous administration while potentially reducing the weekly dose, monitoring hematocrit every 4-6 weeks during the transition, and considering therapeutic phlebotomy if hematocrit remains above 54%. Many clinicians have observed that patients with previously problematic hematocrit elevation on IM testosterone experience normalization or significant improvement after switching to SubQ administration, even when maintaining similar testosterone levels.
The mechanism for this benefit likely involves the more stable testosterone levels avoiding supraphysiological peaks that stimulate excessive erythropoietin production. For men with persistent erythrocytosis despite subcutaneous administration, additional interventions may include further dose reduction, more frequent dosing to minimize peaks, increased hydration, and in some cases, temporary treatment interruption followed by resumption at a lower dose.
Fertility Preservation Considerations
While the route of testosterone administration does not significantly alter the suppression of spermatogenesis, the dosing flexibility offered by subcutaneous injection may facilitate combination protocols for fertility preservation. Men using human chorionic gonadotropin (hCG) concurrently with testosterone to maintain fertility can benefit from the convenience of subcutaneous administration for both medications, as hCG is also typically given subcutaneously.
The ability to use smaller, more frequent doses with subcutaneous testosterone may also allow for lower total weekly doses while maintaining symptom control, potentially reducing the degree of suppression of the hypothalamic-pituitary-gonadal axis. However, all men of reproductive age considering testosterone therapy should discuss fertility preservation options with their healthcare provider before initiating treatment, regardless of administration route.
Body Composition and Injection Site Selection
Subcutaneous testosterone administration is effective across a wide range of body compositions, with clinical studies demonstrating success in patients with BMI ranging from 19.0 to 49.9 kg/m². However, body composition may influence optimal injection site selection and needle length.
Men with lower body fat may prefer the abdomen or outer thighs where subcutaneous tissue is typically adequate, while those with higher body fat percentages have more flexibility in site selection. Very lean individuals may require slightly longer needles to ensure subcutaneous (not intradermal) placement, while those with substantial subcutaneous tissue can comfortably use shorter needles. Site rotation remains critical regardless of body composition to prevent lipohypertrophy and maintain injection site integrity.
Small, firm lumps at injection sites are one of the most common minor issues with subcutaneous testosterone administration. These nodules typically result from localized inflammation, slow absorption, or repeated use of the same injection site. Most resolve spontaneously within 1-2 weeks without intervention.
To minimize lump formation, inject slowly over 15-30 seconds rather than rapidly pushing the plunger, rotate injection sites systematically and avoid using the same location more than once every 2-3 weeks, allow testosterone to warm to room temperature before injection (cold medication can increase tissue reaction), and massage the injection site gently after removing the needle to help distribute the medication.
If lumps persist for more than 2 weeks, become increasingly painful, feel warm to the touch, or show signs of infection (redness, discharge), contact your healthcare provider. Chronic lump formation may indicate the need for improved site rotation, different needle length, or slower injection technique.
Medication Leakage
Occasionally, a small amount of testosterone may leak from the injection site immediately after needle removal. While usually insignificant, consistent leakage can reduce the effective dose. To minimize this issue, inject at a 90-degree angle for better tissue seal, pause for 5-10 seconds after injecting before removing the needle, and apply firm pressure immediately after removing the needle and hold for 30-60 seconds.
The z-track technique—pulling the skin to one side before inserting the needle, then releasing it after removal—can also help prevent leakage by creating an offset path that seals naturally. However, this technique is typically unnecessary with subcutaneous injections and is more commonly used with intramuscular administration.
Difficulty Drawing Up Testosterone
Testosterone suspended in oil can be viscous and difficult to draw through small-gauge needles. Some patients address this by using a larger needle (e.g., 23-25 gauge) to draw up the medication from the vial, then switching to a smaller needle (27-29 gauge) for the actual injection. However, this adds complexity and wastes supplies.
Alternatively, warming the testosterone vial by rolling it between your palms for 1-2 minutes before drawing reduces viscosity significantly. Some men find that storing testosterone at room temperature (if within manufacturer recommendations) rather than refrigerating it makes drawing easier. Drawing slowly and steadily also helps prevent air bubbles and reduces plunger resistance.
Inconsistent Testosterone Levels
If follow-up testosterone levels are unexpectedly low or inconsistent despite regular injections, several factors should be evaluated. Poor injection technique, such as too-shallow injection (intradermal rather than subcutaneous) can reduce absorption, while inconsistent timing of injections can create erratic levels. Medication leakage reducing the effective dose, or injection into sites with lipohypertrophy or scar tissue may also cause poor absorption.
Working with your healthcare provider to review injection technique, verify proper site selection and rotation, consider more frequent dosing to maintain stable levels, and evaluate for factors affecting testosterone metabolism (SHBG levels, body composition changes, concurrent medications) can help identify and resolve the issue.
While current research has focused primarily on weekly subcutaneous administration of testosterone enanthate and cypionate, ongoing research is evaluating longer-acting subcutaneous formulations. A 2019 study examined subcutaneous administration of testosterone undecanoate—a longer-acting ester typically given intramuscularly every 10-12 weeks. The research found that a single subcutaneous dose of 1000 mg testosterone undecanoate produced a slower time to peak concentration compared to intramuscular administration (8.0 vs 3.3 days) while maintaining therapeutic testosterone levels for approximately 104 days.
These findings suggest that subcutaneous administration could potentially extend to less frequent dosing regimens, offering convenience benefits for patients who prefer monthly or quarterly injections. However, the larger volume of medication required for longer-acting formulations presents technical challenges for subcutaneous administration, and further research is needed to establish optimal protocols.
Personalized Dosing Based on Pharmacogenomics
Emerging research in pharmacogenomics may eventually allow clinicians to predict optimal testosterone dosing based on genetic factors affecting metabolism, SHBG levels, and androgen receptor sensitivity. As this field develops, subcutaneous administration's flexibility for dose adjustment and frequent dosing may prove particularly valuable for implementing precision medicine approaches to testosterone therapy.
Understanding genetic variations in enzymes such as 5-alpha reductase, aromatase, and UDP-glucuronosyltransferases could help clinicians predict which patients might benefit from higher or lower doses, more frequent administration, or specific ester formulations. The ease of self-administration with subcutaneous testosterone makes it an ideal delivery method for personalized protocols requiring frequent dosing adjustments.
Integration with Continuous Monitoring Technologies
As wearable health technology advances, continuous or frequent hormone monitoring may become feasible, allowing real-time optimization of testosterone therapy. Subcutaneous administration's compatibility with self-adjustment makes it well-suited for integration with such technologies. Patients could potentially adjust their dose or timing based on continuous feedback, achieving unprecedented precision in hormone optimization while maintaining the convenience and comfort of at-home administration.
• Most Patients Liked Being Switched to Subcutaneous Testosterone Injections – Clinical study findings on patient satisfaction after transitioning to SubQ administration
• Subcutaneous Administration of Testosterone – Overview of subcutaneous testosterone delivery methods and clinical applications
• Subcutaneous TRT Injections Reduce High Hematocrit – Evidence showing lower erythrocytosis rates with subcutaneous testosterone
• Subcutaneous Testosterone Injections: A Safer, Smoother Solution – Comprehensive discussion of safety advantages and implementation strategies
• Subcutaneous vs. Intramuscular Testosterone: Blood Health and Hematocrit Risk – Detailed comparison of hematological effects between delivery methods
• TRT with Subcutaneous Testosterone Injections: A Safe, Practical Option – Evidence-based review of subcutaneous testosterone as a practical alternative
2. Olson J, Schrager SM, Clark LF, et al. Testosterone Therapy With Subcutaneous Injections: A Safe, Practical, and Reasonable Option. J Endocr Soc. 2022;6(4):bvac036.
3. Marks L, Levy M. Erythrocytosis in Subcutaneous Testosterone Replacement Therapy. J Sex Med. 2022;19(7):1101-1106.
4. Rothman MS, Ariel D, Kelley C, et al. Pharmacokinetics, Safety, and Patient Acceptability of Subcutaneous Versus Intramuscular Testosterone Injection for Gender-Affirming Therapy: A Pilot Study. Endocr Pract. 2024;30(9):870-878.
5. Chan F, Yialamas MA, Safer JD. Erythrocytosis Is Rare With Exogenous Testosterone in Gender-Affirming Hormone Therapy. J Clin Endocrinol Metab. 2024;109(5):1285-1291.
6. Nackeeran S, Kohn T, Gonzalez D, et al. The Effect of Route of Testosterone on Changes in Hematocrit: A Systematic Review and Bayesian Network Meta-Analysis of Randomized Trials. J Urol. 2022;207(1):44-51.
7. Reddy R, Diaz P, Blachman-Braun R, et al. Prevalence of Secondary Erythrocytosis in Men Receiving Testosterone Therapy: A Matched-Cohort Analysis of Intranasal Gel, Injections, and Pellets. Can Urol Assoc J. 2023;17(7):E202-E207.
8. Baines HK, Connelly KJ. A Prospective Comparison Study of Subcutaneous and Intramuscular Testosterone Injections in Transgender Male Adolescents. J Pediatr Endocrinol Metab. 2023;36(11):1028-1036.
9. Turner L, Ly LP, Desai R, et al. Pharmacokinetics and Acceptability of Subcutaneous Injection of Testosterone Undecanoate. J Endocr Soc. 2019;3(8):1531-1540.
10. Gittelman M, Jaffe JS, Kaminetsky JC. Safety of a New Subcutaneous Testosterone Enanthate Auto-Injector: Results of a 26-Week Study. J Sex Med. 2019;16(11):1741-1748.
11. Walia R. Testosterone Replacement, Where Are We in 2025? Trends Urol Men's Health. 2025.
12. FDA. XYOSTED (Testosterone Enanthate) Injection Prescribing Information. Updated January 2025.
Before starting, modifying, or discontinuing testosterone therapy, consult with your physician or endocrinologist. Individual responses to testosterone treatment vary, and what works well for one patient may not be appropriate for another. Your healthcare provider can evaluate your specific medical history, symptoms, laboratory values, and treatment goals to determine the most appropriate testosterone formulation, dose, and administration route for your situation.
Regular monitoring of testosterone levels, hematocrit, prostate health, cardiovascular parameters, and other relevant markers is essential for safe and effective testosterone therapy. Never adjust your testosterone dose or switch administration methods without consulting your healthcare provider. If you experience concerning side effects or symptoms while on testosterone therapy, contact your healthcare provider immediately.
Nelson Vergel is a chemical engineer, patient advocate, and author of Built to Survive, Testosterone: A Man's Guide and Beyond Testosterone. With over three decades of experience in men's health advocacy, Nelson has helped thousands of men optimize their health through informed decision-making about testosterone therapy and related treatments.
Visit ExcelMale.com to join the community, explore the extensive forum archives, and access additional resources on testosterone replacement therapy and men's health optimization.
For decades, intramuscular (IM) injections have been the standard method for testosterone delivery, requiring long needles, deeper tissue penetration, and often resulting in discomfort and injection site reactions. However, a growing body of clinical evidence demonstrates that subcutaneous (SubQ) testosterone injections offer a safe, effective, and often preferred alternative for men on testosterone replacement therapy (TRT).
This comprehensive guide examines the science, clinical data, and practical considerations of subcutaneous testosterone administration. You'll learn about the pharmacokinetic advantages, reduced side effect profile, patient satisfaction data, and proper injection techniques that make SubQ testosterone an increasingly popular choice among TRT patients and clinicians. Whether you're considering switching from IM injections or starting TRT for the first time, understanding subcutaneous delivery can help you make informed decisions about your hormone optimization protocol.
Understanding Subcutaneous Testosterone Administration
What Are Subcutaneous Injections?Subcutaneous injections deliver testosterone into the fatty tissue layer just beneath the skin (the hypodermis), rather than deep into muscle tissue as with intramuscular injections. This superficial administration uses shorter, thinner needles—typically insulin syringes with 27-31 gauge needles that are 1/2 inch or less in length—making the injection process significantly more comfortable and easier to self-administer.
The subcutaneous space has different absorption characteristics compared to muscle tissue. While muscle tissue has rich blood supply allowing for rapid absorption, subcutaneous fat tissue provides slower, more sustained release of testosterone. This pharmacokinetic difference translates to more stable testosterone levels with reduced peak-to-trough fluctuations—a critical advantage for many men seeking consistent hormone levels throughout their dosing interval.
Common subcutaneous injection sites include the abdomen (avoiding the area around the belly button), the front and outer portions of the thighs, and the back of the upper arms. These sites offer adequate subcutaneous tissue for injection while being easily accessible for self-administration. Rotating injection sites is essential to prevent tissue irritation and maintain the integrity of the subcutaneous tissue over time.
Historical Context and FDA Approval
While testosterone therapy has been available since the 1930s, subcutaneous administration has only gained widespread clinical attention in the past two decades. The FDA approval of Xyosted (testosterone enanthate subcutaneous injection) in 2018 marked a significant milestone, providing the first FDA-approved subcutaneous testosterone product specifically designed for hypogonadism treatment.
Xyosted uses an autoinjector system delivering 50 mg, 75 mg, or 100 mg of testosterone enanthate weekly. Pharmacokinetic studies demonstrate that this subcutaneous formulation produces steady serum testosterone concentrations with median peak levels occurring approximately 12 hours post-dose, followed by a slow decline over the dosing interval. However, many clinicians and patients have also successfully adapted traditional testosterone cypionate and enanthate—originally formulated for intramuscular use—for subcutaneous administration using standard insulin syringes.
Clinical Evidence: Efficacy and Pharmacokinetics
Comparable Efficacy to Intramuscular AdministrationMultiple clinical studies have established that subcutaneous testosterone administration achieves therapeutic testosterone levels comparable to intramuscular injections. A landmark 2017 study published in the Journal of Clinical Endocrinology & Metabolism evaluated 63 transgender men receiving weekly subcutaneous testosterone cypionate or enanthate at doses of 50-150 mg. The study found that both total and free testosterone concentrations were consistently maintained within the normal adult male range, with efficacy demonstrated across a wide range of body mass index values (19.0 to 49.9 kg/m²).
A 2024 pilot study comparing pharmacokinetics and patient acceptability of subcutaneous versus intramuscular testosterone found that SubQ administration resulted in similar testosterone exposure while offering improved patient satisfaction. Importantly, the research demonstrated that subcutaneous injection produces more stable testosterone levels with reduced peak-to-trough fluctuations compared to the supraphysiological peaks often seen with intramuscular administration.
The median weekly dose for subcutaneous administration typically ranges from 50-100 mg, which is often lower than the traditional 100-200 mg doses used for biweekly intramuscular injections. This dose reduction is possible due to improved bioavailability and more consistent absorption from subcutaneous tissue. Studies indicate that therapeutic serum testosterone concentrations can be maintained with approximately 75% of the typical intramuscular dose when administered subcutaneously on a weekly basis.
Pharmacokinetic Advantages
The pharmacokinetic profile of subcutaneous testosterone differs meaningfully from intramuscular administration. Research demonstrates that subcutaneous injection of testosterone enanthate produces a slower time to peak concentration (approximately 8.0 days for SubQ versus 3.3 days for IM), while maintaining similar overall testosterone exposure. This slower, more sustained release pattern results in more physiologic testosterone levels that better mimic endogenous production.
Short-acting intramuscular testosterone formulations (cypionate and enanthate) are associated with rapid increases in serum testosterone, often reaching supraphysiological levels within days of injection, followed by a return to baseline by 10-14 days and potential decline to subphysiological levels by 3 weeks if not re-dosed. These dramatic fluctuations can contribute to mood swings, energy variations, and increased side effects. In contrast, subcutaneous administration provides more consistent testosterone levels throughout the dosing interval, potentially reducing these cyclical symptoms.
Studies examining dihydrotestosterone (DHT) and estradiol levels after subcutaneous injection find that these testosterone metabolites increase in a similar manner regardless of administration route. Importantly, subcutaneous testosterone enanthate maintains stable DHT and estradiol concentrations with minimal fluctuations, suggesting that the conversion of testosterone to its metabolites occurs consistently throughout the dosing period.
Safety Profile and Reduced Hematocrit Risk
Significantly Lower Erythrocytosis RatesOne of the most compelling advantages of subcutaneous testosterone administration is the significantly reduced risk of erythrocytosis (elevated hematocrit). Erythrocytosis is one of the most common adverse effects of testosterone therapy, with rates ranging from 5-66% in men receiving intramuscular testosterone—the wide range reflecting differences in dosing, frequency, and patient populations across studies.
A 2022 retrospective study specifically evaluated erythrocytosis rates in 94 cisgender men receiving subcutaneous testosterone cypionate. The study found that 32% of men developed new-onset erythrocytosis (hematocrit ≥53%), which represents a substantial reduction compared to the 40-66% rates commonly reported with intramuscular administration. This clinically meaningful difference suggests that the route of administration significantly influences red blood cell production independent of testosterone dose or exposure.
A comprehensive 2024 study examining erythrocytosis in transgender patients found that intramuscular testosterone was associated with significantly higher hematocrit levels compared to transdermal formulations, even after controlling for testosterone levels. While the subcutaneous group was too small for statistical comparison in this study, the pattern suggested that route of administration plays an independent role in hematocrit elevation beyond simply the amount of testosterone delivered.
The mechanism underlying this reduced erythrocytosis risk likely relates to the more stable testosterone levels achieved with subcutaneous administration. Supraphysiological testosterone peaks—common with intramuscular injections—may trigger more aggressive erythropoietin stimulation and hepcidin suppression, leading to increased red blood cell production. By avoiding these peaks, subcutaneous administration may provide a safer erythropoietic profile while maintaining therapeutic testosterone exposure.
Injection Site Reactions and Tolerability
Subcutaneous testosterone administration is generally well-tolerated with minimal local adverse effects. In the 2017 transgender study of 63 patients receiving subcutaneous testosterone for up to 43 months, only 9 participants (14%) reported injection site reactions. These included minor, self-limited events such as small painless nodules that resolved within 2 days, transient urticaria lasting up to 3 days, mild local inflammation, and one case of self-limited cellulitis.
Notably, these reaction rates are considerably lower than those commonly reported with intramuscular injections, which frequently cause pain, bruising, and muscle soreness at injection sites. The smaller needle gauge, shorter needle length, and superficial injection technique all contribute to improved tolerability. Proper injection technique, site rotation, and appropriate needle selection further minimize the risk of local reactions.
Patient Satisfaction and Preference
Strong Patient Preference for Subcutaneous AdministrationPatient satisfaction data consistently demonstrates a strong preference for subcutaneous over intramuscular testosterone administration. In the 2017 Journal of Clinical Endocrinology & Metabolism study, 22 patients who had previously been receiving intramuscular testosterone were switched to subcutaneous administration. Among these patients, 20 (91%) expressed a marked preference for subcutaneous injections, while 2 (9%) reported a mild preference, and notably, zero patients preferred returning to intramuscular injections.
The reasons for this overwhelming preference are multifaceted. Subcutaneous injections involve less pain during administration, require smaller and shorter needles, are easier to self-administer without assistance, offer more convenient injection sites that patients can reach themselves, and produce fewer injection site reactions such as bruising or soreness. These practical advantages translate to improved treatment adherence—a critical factor in achieving optimal therapeutic outcomes with long-term testosterone therapy.
A 2023 prospective comparison study of subcutaneous versus intramuscular testosterone in transgender adolescents found that both methods were equally effective in achieving target testosterone levels and producing desired masculinizing effects. However, the subcutaneous group reported higher satisfaction scores, with particular emphasis on the reduced discomfort and increased autonomy in self-administration. This finding suggests that the preference for subcutaneous administration extends across different age groups and patient populations.
Improved Treatment Adherence
The ease of self-administration with subcutaneous injections has important implications for treatment adherence. Traditional intramuscular injections—particularly into the gluteal muscles—often require assistance from healthcare providers or family members, necessitating frequent clinic visits or complicated arrangements. This dependence can create significant barriers to consistent therapy.
Subcutaneous administration eliminates many of these barriers. The accessible injection sites (abdomen, thighs, upper arms), smaller needles, and simpler technique allow most patients to confidently self-inject after brief training. This autonomy not only improves convenience but also empowers patients to maintain consistent dosing schedules, leading to better therapeutic outcomes. Studies suggest that the improved adherence associated with subcutaneous testosterone may contribute to its favorable safety profile and patient satisfaction.
Practical Implementation: Dosing and Administration
Recommended Dosing ProtocolsClinical experience and published research suggest that weekly subcutaneous testosterone dosing of 50-100 mg effectively maintains therapeutic testosterone levels in most men. The FDA-approved Xyosted product uses a starting dose of 75 mg weekly, with dose adjustments based on trough testosterone concentrations measured after 6 weeks of treatment. For patients using compounded testosterone cypionate or enanthate for subcutaneous administration, a typical starting dose is 50-75 mg weekly.
Some clinicians and patients have adopted more frequent dosing schedules—including twice-weekly or even daily microdosing protocols—to further stabilize testosterone levels. Daily microdosing typically involves subcutaneous injections of 10-20 mg using insulin syringes. Advocates of this approach report benefits including even more stable testosterone levels, reduced estradiol fluctuations, and potentially lower aromatase activity. However, daily injections require greater commitment and may not be necessary or preferred by all patients.
Dosing should always be individualized based on patient response, symptom improvement, and laboratory monitoring. Factors influencing optimal dose include body weight, metabolism, SHBG levels, injection frequency, and individual treatment goals. Regular monitoring of total testosterone, free testosterone, estradiol, and hematocrit allows for appropriate dose adjustments to maintain target levels while minimizing side effects.
Proper Injection Technique
Correct subcutaneous injection technique is essential for maximizing comfort, efficacy, and safety. The recommended approach involves the following steps:
Site Selection and Preparation: Choose an appropriate injection site—abdomen (avoiding 2 inches around the belly button), front/outer thigh, or back of upper arm. Clean the area with an alcohol wipe and allow it to air dry completely. Gather supplies including testosterone vial, insulin syringe (typically 27-31 gauge, 1/2 inch or shorter), alcohol wipes, and a sharps container.
Drawing Up Medication: Draw air into the syringe equal to your dose. Insert the needle into the testosterone vial and inject the air. Invert the vial and slowly draw up the prescribed dose. Remove air bubbles by tapping the syringe and gently pushing the plunger until a small amount of testosterone appears at the needle tip.
Injection Procedure: Pinch the skin at the injection site to create a fold of fatty tissue. Insert the needle at a 45-90 degree angle (90 degrees is typically used with shorter needles). Inject slowly and steadily—rushing can increase the risk of lumps or irritation. Remove the needle quickly and apply gentle pressure with a clean cotton ball or gauze.
Site Rotation: Consistently rotate injection sites to prevent tissue damage and lipohypertrophy (lumps of fatty tissue buildup). Keep a simple injection log noting the date, location, and any reactions. This helps ensure systematic rotation and identifies any problematic sites.
Safety Considerations: Never reuse needles or syringes. Dispose of all sharps in an approved sharps container. If you experience warmth, redness, increasing pain, or signs of infection at an injection site, contact your healthcare provider. Small, temporary lumps or minor bruising are common and usually resolve within a few days.
Equipment and Supplies
For subcutaneous testosterone administration, patients typically use insulin syringes, which combine the needle and syringe in a single unit. Common specifications include:
Needle Gauge: 27-31 gauge needles are standard. Higher gauge numbers indicate thinner needles, which cause less discomfort. For testosterone oils, 27-29 gauge generally provides an optimal balance between comfort and ease of drawing up the medication.
Needle Length: 1/2 inch (12.7mm) or 5/16 inch (8mm) needles are most common. Shorter needles work well for most patients, though individuals with very low body fat may need 1/2 inch, while those with higher body fat can use shorter options.
Syringe Volume: 0.5 mL or 1 mL insulin syringes are typically adequate for weekly doses of 50-100 mg. For microdosing protocols with smaller daily doses, 0.3 mL syringes may be more convenient and allow for more precise measurement.
Subcutaneous vs. Intramuscular: Direct Comparison
The following table summarizes the key differences between subcutaneous and intramuscular testosterone administration based on clinical evidence:Parameter | Subcutaneous (SubQ) | Intramuscular (IM) |
| Needle Size | 27-31 gauge, 1/2 inch or less | 20-23 gauge, 1-1.5 inches |
Injection Sites | Abdomen, thighs, upper arms | Glutes, thighs, deltoids |
Typical Weekly Dose | 50-100 mg | 100-200 mg (often biweekly) |
Pain/Discomfort | Minimal to none | Moderate, potential soreness |
Testosterone Stability | More stable, smaller peaks | Higher peaks, more fluctuation |
Erythrocytosis Risk | Lower (approximately 32%) | Higher (40-66%) |
Self-Administration | Easy, most patients successful | Difficult for some sites |
Patient Preference | Strongly preferred (91%+) | Traditional standard |
Cost | Comparable or lower | Low (generic available) |
Special Considerations for TRT Patients
Transitioning from Intramuscular to SubcutaneousMen currently on intramuscular testosterone who wish to transition to subcutaneous administration should work with their healthcare provider to adjust dosing appropriately. A common approach involves reducing the total weekly testosterone dose by approximately 25-30% when switching from IM to SubQ, then adjusting based on follow-up laboratory testing.
For example, a patient on 200 mg intramuscular testosterone every two weeks (100 mg per week average) might transition to 75 mg subcutaneous weekly. Initial follow-up testing at 4-6 weeks allows for dose optimization based on trough testosterone levels, symptom response, and side effect profile. Most patients find that the more stable testosterone levels with subcutaneous administration require less frequent dose adjustments once optimal dosing is established.
During the transition period, patients should monitor for changes in energy, mood, libido, and other testosterone-dependent symptoms. Some men report improved symptom stability with the elimination of the peak-trough cycling associated with less frequent intramuscular injections. However, the transition should be gradual, and patience is necessary as it may take 6-8 weeks to reach stable testosterone levels with a new protocol.
Managing Elevated Hematocrit
For men who have developed erythrocytosis on intramuscular testosterone, transitioning to subcutaneous administration may help reduce hematocrit levels. The clinical evidence demonstrating lower erythrocytosis rates with SubQ testosterone makes this an attractive option for patients who have had to interrupt or discontinue therapy due to elevated hematocrit.
A typical management strategy involves switching to subcutaneous administration while potentially reducing the weekly dose, monitoring hematocrit every 4-6 weeks during the transition, and considering therapeutic phlebotomy if hematocrit remains above 54%. Many clinicians have observed that patients with previously problematic hematocrit elevation on IM testosterone experience normalization or significant improvement after switching to SubQ administration, even when maintaining similar testosterone levels.
The mechanism for this benefit likely involves the more stable testosterone levels avoiding supraphysiological peaks that stimulate excessive erythropoietin production. For men with persistent erythrocytosis despite subcutaneous administration, additional interventions may include further dose reduction, more frequent dosing to minimize peaks, increased hydration, and in some cases, temporary treatment interruption followed by resumption at a lower dose.
Fertility Preservation Considerations
While the route of testosterone administration does not significantly alter the suppression of spermatogenesis, the dosing flexibility offered by subcutaneous injection may facilitate combination protocols for fertility preservation. Men using human chorionic gonadotropin (hCG) concurrently with testosterone to maintain fertility can benefit from the convenience of subcutaneous administration for both medications, as hCG is also typically given subcutaneously.
The ability to use smaller, more frequent doses with subcutaneous testosterone may also allow for lower total weekly doses while maintaining symptom control, potentially reducing the degree of suppression of the hypothalamic-pituitary-gonadal axis. However, all men of reproductive age considering testosterone therapy should discuss fertility preservation options with their healthcare provider before initiating treatment, regardless of administration route.
Body Composition and Injection Site Selection
Subcutaneous testosterone administration is effective across a wide range of body compositions, with clinical studies demonstrating success in patients with BMI ranging from 19.0 to 49.9 kg/m². However, body composition may influence optimal injection site selection and needle length.
Men with lower body fat may prefer the abdomen or outer thighs where subcutaneous tissue is typically adequate, while those with higher body fat percentages have more flexibility in site selection. Very lean individuals may require slightly longer needles to ensure subcutaneous (not intradermal) placement, while those with substantial subcutaneous tissue can comfortably use shorter needles. Site rotation remains critical regardless of body composition to prevent lipohypertrophy and maintain injection site integrity.
Troubleshooting Common Issues
Injection Site Lumps and NodulesSmall, firm lumps at injection sites are one of the most common minor issues with subcutaneous testosterone administration. These nodules typically result from localized inflammation, slow absorption, or repeated use of the same injection site. Most resolve spontaneously within 1-2 weeks without intervention.
To minimize lump formation, inject slowly over 15-30 seconds rather than rapidly pushing the plunger, rotate injection sites systematically and avoid using the same location more than once every 2-3 weeks, allow testosterone to warm to room temperature before injection (cold medication can increase tissue reaction), and massage the injection site gently after removing the needle to help distribute the medication.
If lumps persist for more than 2 weeks, become increasingly painful, feel warm to the touch, or show signs of infection (redness, discharge), contact your healthcare provider. Chronic lump formation may indicate the need for improved site rotation, different needle length, or slower injection technique.
Medication Leakage
Occasionally, a small amount of testosterone may leak from the injection site immediately after needle removal. While usually insignificant, consistent leakage can reduce the effective dose. To minimize this issue, inject at a 90-degree angle for better tissue seal, pause for 5-10 seconds after injecting before removing the needle, and apply firm pressure immediately after removing the needle and hold for 30-60 seconds.
The z-track technique—pulling the skin to one side before inserting the needle, then releasing it after removal—can also help prevent leakage by creating an offset path that seals naturally. However, this technique is typically unnecessary with subcutaneous injections and is more commonly used with intramuscular administration.
Difficulty Drawing Up Testosterone
Testosterone suspended in oil can be viscous and difficult to draw through small-gauge needles. Some patients address this by using a larger needle (e.g., 23-25 gauge) to draw up the medication from the vial, then switching to a smaller needle (27-29 gauge) for the actual injection. However, this adds complexity and wastes supplies.
Alternatively, warming the testosterone vial by rolling it between your palms for 1-2 minutes before drawing reduces viscosity significantly. Some men find that storing testosterone at room temperature (if within manufacturer recommendations) rather than refrigerating it makes drawing easier. Drawing slowly and steadily also helps prevent air bubbles and reduces plunger resistance.
Inconsistent Testosterone Levels
If follow-up testosterone levels are unexpectedly low or inconsistent despite regular injections, several factors should be evaluated. Poor injection technique, such as too-shallow injection (intradermal rather than subcutaneous) can reduce absorption, while inconsistent timing of injections can create erratic levels. Medication leakage reducing the effective dose, or injection into sites with lipohypertrophy or scar tissue may also cause poor absorption.
Working with your healthcare provider to review injection technique, verify proper site selection and rotation, consider more frequent dosing to maintain stable levels, and evaluate for factors affecting testosterone metabolism (SHBG levels, body composition changes, concurrent medications) can help identify and resolve the issue.
Future Directions and Emerging Research
Long-Acting Subcutaneous FormulationsWhile current research has focused primarily on weekly subcutaneous administration of testosterone enanthate and cypionate, ongoing research is evaluating longer-acting subcutaneous formulations. A 2019 study examined subcutaneous administration of testosterone undecanoate—a longer-acting ester typically given intramuscularly every 10-12 weeks. The research found that a single subcutaneous dose of 1000 mg testosterone undecanoate produced a slower time to peak concentration compared to intramuscular administration (8.0 vs 3.3 days) while maintaining therapeutic testosterone levels for approximately 104 days.
These findings suggest that subcutaneous administration could potentially extend to less frequent dosing regimens, offering convenience benefits for patients who prefer monthly or quarterly injections. However, the larger volume of medication required for longer-acting formulations presents technical challenges for subcutaneous administration, and further research is needed to establish optimal protocols.
Personalized Dosing Based on Pharmacogenomics
Emerging research in pharmacogenomics may eventually allow clinicians to predict optimal testosterone dosing based on genetic factors affecting metabolism, SHBG levels, and androgen receptor sensitivity. As this field develops, subcutaneous administration's flexibility for dose adjustment and frequent dosing may prove particularly valuable for implementing precision medicine approaches to testosterone therapy.
Understanding genetic variations in enzymes such as 5-alpha reductase, aromatase, and UDP-glucuronosyltransferases could help clinicians predict which patients might benefit from higher or lower doses, more frequent administration, or specific ester formulations. The ease of self-administration with subcutaneous testosterone makes it an ideal delivery method for personalized protocols requiring frequent dosing adjustments.
Integration with Continuous Monitoring Technologies
As wearable health technology advances, continuous or frequent hormone monitoring may become feasible, allowing real-time optimization of testosterone therapy. Subcutaneous administration's compatibility with self-adjustment makes it well-suited for integration with such technologies. Patients could potentially adjust their dose or timing based on continuous feedback, achieving unprecedented precision in hormone optimization while maintaining the convenience and comfort of at-home administration.
Related ExcelMale Forum Discussions
Explore these community discussions for additional insights and real-world experiences with subcutaneous testosterone administration:• Most Patients Liked Being Switched to Subcutaneous Testosterone Injections – Clinical study findings on patient satisfaction after transitioning to SubQ administration
• Subcutaneous Administration of Testosterone – Overview of subcutaneous testosterone delivery methods and clinical applications
• Subcutaneous TRT Injections Reduce High Hematocrit – Evidence showing lower erythrocytosis rates with subcutaneous testosterone
• Subcutaneous Testosterone Injections: A Safer, Smoother Solution – Comprehensive discussion of safety advantages and implementation strategies
• Subcutaneous vs. Intramuscular Testosterone: Blood Health and Hematocrit Risk – Detailed comparison of hematological effects between delivery methods
• TRT with Subcutaneous Testosterone Injections: A Safe, Practical Option – Evidence-based review of subcutaneous testosterone as a practical alternative
Key References
1. Spratt DI, Stewart II, Savage C, et al. Subcutaneous Injection of Testosterone Is an Effective and Preferred Alternative to Intramuscular Injection: Demonstration in Female-to-Male Transgender Patients. J Clin Endocrinol Metab. 2017;102(7):2349-2355.2. Olson J, Schrager SM, Clark LF, et al. Testosterone Therapy With Subcutaneous Injections: A Safe, Practical, and Reasonable Option. J Endocr Soc. 2022;6(4):bvac036.
3. Marks L, Levy M. Erythrocytosis in Subcutaneous Testosterone Replacement Therapy. J Sex Med. 2022;19(7):1101-1106.
4. Rothman MS, Ariel D, Kelley C, et al. Pharmacokinetics, Safety, and Patient Acceptability of Subcutaneous Versus Intramuscular Testosterone Injection for Gender-Affirming Therapy: A Pilot Study. Endocr Pract. 2024;30(9):870-878.
5. Chan F, Yialamas MA, Safer JD. Erythrocytosis Is Rare With Exogenous Testosterone in Gender-Affirming Hormone Therapy. J Clin Endocrinol Metab. 2024;109(5):1285-1291.
6. Nackeeran S, Kohn T, Gonzalez D, et al. The Effect of Route of Testosterone on Changes in Hematocrit: A Systematic Review and Bayesian Network Meta-Analysis of Randomized Trials. J Urol. 2022;207(1):44-51.
7. Reddy R, Diaz P, Blachman-Braun R, et al. Prevalence of Secondary Erythrocytosis in Men Receiving Testosterone Therapy: A Matched-Cohort Analysis of Intranasal Gel, Injections, and Pellets. Can Urol Assoc J. 2023;17(7):E202-E207.
8. Baines HK, Connelly KJ. A Prospective Comparison Study of Subcutaneous and Intramuscular Testosterone Injections in Transgender Male Adolescents. J Pediatr Endocrinol Metab. 2023;36(11):1028-1036.
9. Turner L, Ly LP, Desai R, et al. Pharmacokinetics and Acceptability of Subcutaneous Injection of Testosterone Undecanoate. J Endocr Soc. 2019;3(8):1531-1540.
10. Gittelman M, Jaffe JS, Kaminetsky JC. Safety of a New Subcutaneous Testosterone Enanthate Auto-Injector: Results of a 26-Week Study. J Sex Med. 2019;16(11):1741-1748.
11. Walia R. Testosterone Replacement, Where Are We in 2025? Trends Urol Men's Health. 2025.
12. FDA. XYOSTED (Testosterone Enanthate) Injection Prescribing Information. Updated January 2025.
Medical Disclaimer
This article is provided for informational and educational purposes only and is not intended as medical advice. The information presented should not be used for diagnosing or treating health conditions or prescribing medications. Testosterone replacement therapy is a medical treatment that requires supervision by a qualified healthcare provider.Before starting, modifying, or discontinuing testosterone therapy, consult with your physician or endocrinologist. Individual responses to testosterone treatment vary, and what works well for one patient may not be appropriate for another. Your healthcare provider can evaluate your specific medical history, symptoms, laboratory values, and treatment goals to determine the most appropriate testosterone formulation, dose, and administration route for your situation.
Regular monitoring of testosterone levels, hematocrit, prostate health, cardiovascular parameters, and other relevant markers is essential for safe and effective testosterone therapy. Never adjust your testosterone dose or switch administration methods without consulting your healthcare provider. If you experience concerning side effects or symptoms while on testosterone therapy, contact your healthcare provider immediately.
About ExcelMale
ExcelMale.com is a comprehensive men's health forum with over 24,000 members dedicated to testosterone replacement therapy, hormone optimization, and sexual health. Founded by Nelson Vergel, the community provides evidence-based information, peer support, and practical guidance for men navigating hormone therapy and related health concerns.Nelson Vergel is a chemical engineer, patient advocate, and author of Built to Survive, Testosterone: A Man's Guide and Beyond Testosterone. With over three decades of experience in men's health advocacy, Nelson has helped thousands of men optimize their health through informed decision-making about testosterone therapy and related treatments.
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