Erectile dysfunction and duration of finasteride treatment

The results of the study show that only 1.4% of men exposed to inhibitors of 5α-reductase, finasteride and dutasteride developed erectile dysfunction that continued for at least 90 days after discontinuing treatment.

Case reports have linked persistent erectile dysfunction with the use of 5α-reductase inhibitors, finasteride and dutasteride. However, it has been argued that the risk of adverse sexual effects does not increase with prolonged exposure to the drugs and the effects are resolved in men who stop taking them.

To assess this, a team of researchers studied data from 11,909 men who took a 5α-reductase inhibitor and had no history of erectile dysfunction.
Overall, 167 (1.4%) men developed persistent erectile dysfunction that continued for at least 90 days after discontinuation of treatment. In multivariable analysis, the duration of exposure to a 5α-reductase inhibitor was a more accurate predictor of persistent erectile dysfunction than many known risk factors, including age, hypertension, and depression.

Writing in PeerJ (online, 9 March 2017), the researchers say their findings will be of particular interest to prescribers or patients considering treatment with a 5α-reductase inhibitor.