When your doctor recommends a medication that you will take for a long time, it makes sense to find out what side effects it may cause. Some men were alarmed to discover that their prostate medication could make the penis shrink.
Do Prostate Medicines Make Penis Shrink?
Q. Taking Avodart triggered the onset of both erectile dysfunction and reduced ejaculate for me. I took it for two years; my prostate did not shrink, but my penis did.
These sexual side effects linger. Five years later, I still have ED and low ejaculate. The symptom of frequent nightly urination, however, has ceased to be a problem. Will the sexual side effects ever go away?
Drugs for Prostate Enlargement:
A. Medications that shrink the prostate include dutasteride (Avodart) and finasteride (Proscar). These drugs are prescribed to treat symptoms of benign prostate enlargement. Lower dose finasteride (Propecia) is also prescribed for male pattern baldness.
A study published in the Journal of Sexual Medicine (Nov. 2012) reported persistent sexual side effects in men who took finasteride. These included reduced sexual arousal, lower ejaculate volume, erection difficulties and inability to reach orgasm. The study subjects also complained of smaller penis size and reduced sensation. It is not clear how long these complications may last.
Dutasteride is likely to have similar side effects (Urology, March 2014). In fact, a study in rats demonstrated that dutasteride does affect the penis as well as the prostate (Andrology, March 2017). A meta-analysis revealed that many men treated for benign prostate enlargement with one of these medications frequently experience adverse sexual side effects (Journal of Sexual Medicine, Sep. 2016).
Revised 8/16/18