I read or heard of multiple guys trying to replicate Mazzarella study and still got sides. 0.005% is 3mg of finasteride in an entire bottle of minoxidil, still this leads to accumulation with 2 times per day application.
Only concentration i've read about that can be used daily without greatly affecting dht, is 0.0016%, which is 1mg finasteride in a 60ml bottle of minoxidil. quote from user " I have used 0.00166_% x ~2 ml daily for months without change in serum DHT."
source
Same user, tried to add dutasteride to this mix with a concentration of 0.0004% that's like 0.25mg per entire bottle and his serum DHT lowered with ~50-60% after months of use.This shows how much more powerful dutasteride is
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