Drug initially upregulates Testosterone production by 10-20% to compensate for lack of DHT.
Problem is since T cannot convert into DHT anymore, it aromatizes into Estradiol (estrogen) instead. Over time this can shift the androgen/estrogen ration a man’s body to be in favor of estrogens, leading to gynecomastia and a host of other unpleasant side effects.
The initial burst in libido is often temporary and eventually, some guys find they start losing it for such reasons. Elevated estrogen can also increase SHBG, which binds to Free Testosterone (2% of which is available to the body at any one time), thus lowering the amount of Free T that’s bioactively available.
If you plan on continuing Finasteride without issue, I wish you luck, but I would recommend against it based on the scientific materials posted on this forum.
Cheers.