The FDA has approved Cialis (tadalafil) to treat the signs and symptoms of benign prostatic hyperplasia (BPH), a condition in which the prostate gland becomes enlarged, and for the treatment of BPH and erectile dysfunction, when the conditions occur simultaneously. Cialis was approved in 2003 for the treatment of ED.

The severity of symptoms of BPH can be measured using the international prostate symptom score (IPSS). In two clinical trials, men with BPH who took 5 mg of Cialis once daily experienced a statistically significant improvement in their symptoms of BPH compared to men who were treated with placebo. The trials based their findings on a reduction in total IPSS scores.

In a third study, men who experienced both ED and BPH and who took 5 mg of Cialis once daily had improvement in both their symptoms of BPH and in their ED compared to men who were treated with placebo. The improvement in ED was measured using the ED domain score of the international index of erectile function.