Finasteride is a 5-alpha-reductase inhibitor which reduces the level of Dihydrotestosterone (DHT) type-2. It is used to treat men with benign prostatic hyperplasia or male pattern hair loss. Both effects will only last as long as the medicine is taken. When the level of DHT is lower, the prostate will decrease it's size which reduce symptoms like a decreased flow of urination, have difficulty urinating and the need to get up at night to urinate. Another effect by a reduced level of DHT type-2 will stop the hair loss on the scalp, in many cases it can regrow already lost hair as well. Finasteride cannot stop or regrow hair on the receding hairline due in this area DHT type-1 is active. This type of DHT can only be reduced by Dutasteride which is a more stronger 5-alpha-reductase inhibitor than Finasteride.
The following side effects are ordered by descending occurrence.