My libido has gotten worse since trt. Didn’t have libido issues before, now I feel like it’s just not really there, kinda feel numb in that department. What should I look into with my dr? I’ve been doing 100mg test cyp for 6mos, inject once a week. My testosterone went from 274 to 775 at trough and estradiol is now 24 (don’t have before numbers).

AlphaMD's Answer

Libido issues can unfortunately be difficult to pin down sometimes because there are many factors, both intrinsic and extrinsic, that affect it.

It seems like your testosterone and estradiol are ideal, so it doesn’t appear to be a problem with the sex hormones.

Libido is primarily governed by dopamine. So bear in mind that this is a neurotransmitter that there is no test for, though there are medications to increase it known as dopamine agonists. There are two types: ergoline and non-ergoline. You may have heard of cabergoline (ergoline) or pramipexole (non-ergoline). These medications are actually primarily used for Parkinson's Disease, but funnily enough, they both have warnings on their labels about the increased libido. In my over 16 years treating both men and women with libido issues, I have never seen these medicines not significantly improve libido.

There is no blood test for dopamine levels, so typically if dopamine is felt to be the cause, then a trial of caber or prami is used to see if there is improvement. Symptom improvement tends to be rather quick, usually within a few days.

After dopamine, the rest of the physiologic factors are hormonal, and in order they are testosterone, oxytocin, and then estrogen. Each of these has been scientifically proven to have effect on libido. With the exception of oxytocin, each of these can be measured with commercially available blood tests.

Prolactin outside of the normal range (high or low) also seems to have some effect on libido. Some men who start TRT have a spike in prolactin. This is usually due to an undiagnosed prolactinoma (a benign pituitary tumor). Checking your prolactin is always a smart choice when you notice worse libido after starting TRT.

Either way, you should follow up with your doctor to evaluate further.