Youll need to take finasteride for 3 months before it has its full effect, but even if ya dont have 3 months to wait, it would probably still be better than nothing.1mg a day will reduce DHT by 60%, 1.25mg a day will reduce DHT by 65% and 5mg a day reduces it by 70%, but higher doses like 5mg a day can affect labido and stuff, so 1.25mg a day is probably best. It should help with the prop but i dont think it will help much for the tren. I dont think using it will hinder gains by any noticable or significant amount.

Dutasteride is similar to finasteride, but much better. It can reduce DHT levels by 90-93% Ive read. Im not sure about dosages or anything, but ya might want to look into it if youre worried. Also using nizoral shampoo every 3 days could also help. Good luck