I see that interaction mentioned on this site:
Loperamide; Simethicone: (Moderate) The plasma concentration of loperamide, a P-glycoprotein (P-gp) substrate, may be increased when administered concurrently with testosterone, a P-gp inhibitor. If these drugs are used together, monitor for loperamide-associated adverse reactions, such as CNS effects and cardiac toxicities (i.e., syncope, ventricular tachycardia, QT prolongation, torsade de pointes, cardiac arrest).
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You might consider checking testosterone levels sooner rather than later. Ideally get total testosterone, SHBG and free testosterone by equilibrium dialysis. Total testosterone and SHBG can be used to estimate free T if you don't want to spring for the free T test.
While your starting TRT dose isn't unreasonable, if you are a slower metabolizer then you could still have quite high serum levels. For example, at that dose I would have total testosterone averaging over 1,100 ng/dL, which is pushing double what I normally run.
Depending on your test results it seems as though the problem could be ameliorated through a dose reduction in one or both of the drugs.
