Prolactin

[bobcat]

My prolactin is a bit high. 18.5 when 17.7 is high normal range. What does this mean? What should I do about it? (My kaiser endo wants me to go off hcg. Hell, no. I just got my balls back.)

 

[Nelson Vergel]

If you testosterone blood levels are adequate and you have no liquid coming out of your nipples, I would not worry. (your level is low so that should not be a problem)

I would monitor it every few weeks if it was me just to see if there is a trend.

 

[Nelson Vergel]

Substantial elevation in prolactin (>150 ng/mL) in a nonpuerperal state usually indicates a pituitary tumor. Good correlation exists between radiographic estimates of tumor size and prolactin levels, and very high levels of prolactin are associated with larger tumors. Prolactinomas are classified as microade-nomas (<10 mm) and macroadenomas (>10 mm). The finding of a substantial elevation in serum prolactin in association with a pituitary lesion larger than 10 mm by radiographic analysis supports the diagnosis of a macroprolactinoma.

Modest levels of prolactin elevation (25&#8211;100 ng/mL) may be associated with several diagnoses. All other causes of hyper-prolactinemia should be excluded before a tumor is considered. Primary hypothyroidism and pregnancy should be excluded. Chronic renal disease is associated with elevations in prolactin, probably because of altered metabolism or clearance of prolac-tin or decreases in dopaminergic tone.44 Hemodialysis does not usually reverse the hyperprolactinemia.

Multiple pharmacologic causes of hyperprolactinemia are found. Ingestion of phenothiazines and other neuroleptics is a common cause for elevations in serum prolactin.44a One diagnostic problem is the evaluation of patients with psychiatric disease who are receiving phenothiazines and are found to have an elevated prolactin level. A magnetic resonance image (MRI) should be obtained for patients whose prolactin levels are above 100 ng/mL. Levels lower than 100 ng/mL are consistent with neuroleptic administration, and a scan is unnecessary unless other symptoms suggest a pituitary tumor. This strategy is based on the finding that most patients receiving neuroleptics with modest prolactin elevations have no evidence of a pituitary abnormality on MRI. Other pharmacologic agents associated with hyperprolactinemia include reserpine, a-methyldopa, cimetidine, and opiates. http://medtextfree.wordpress.com/201...its-disorders/


Low thyroid and kidney function can also increase prolactin levels. A recent high protein meal and exercise before the test can also increase prolactin, so keep that in mind when counseling patients before the test.


I am not horribly convinced that treating prolactin levels that are above 18 ng/ml (same as microgram/L) with cabergoline, but studies seem to support it.

http://jcem.endojournals.org/content/89/2/621.short


http://www.nature.com/ijir/journal/v19/n1/abs/3901483a.html


I would not give more than 0.2-0.5 mg once per week to men with high prolactin due to the potential of bringing it down too much and causing ED (both high and low can cause ED).

 

[OMI100]

Interesting study done in Japan:
"In conclusion, associations between serum PRL levels within the physiological range and HOMA-R were found to be positive for men. These findings indicate that higher serum PRL levels within the physiological range seem to be associated with insulin resistance in men in this non-diabetic Japanese population. Further studies are required to determine whether such findings are applicable to other ethnicities and whether the associations can be exploited to predict the risk for the incidence of type 2 diabetes mellitus."
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5383244/