I'm no expert but, from what I understand, you should never use finasteride with trenbolone. The word on the street is that tren is a nandrolone analogue and using finasteride with fina could actually accelerate hairloss if you're prone to it.
I asked the same question yesterday, noone posted, so I assume no one who viewed the post had a definite answer. I did do a search and what I got from reading was to stop using proscar while on fina. But not 100% sure.
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