Tadalafil belongs to a group of medicines called phosphodiesterase 5 PDE5 inhibitors. It is an age-associated prostate gland enlargement which can cause problems with urination. This leads to swelling and squeezing of the urethra and limits the urine flow. It could be a sign of physical or psychological conditions such as fear of sexual failure, anxiety, depression, low self-esteem, or stress. In trials of the drug, individuals taking Cialis saw a significant reduction in the frequency and urgency of urination and improved urine flow. Share intimate time with your partner.Cialis is Food and Drug Administration (FDA) approved to treat erectile dysfunction (ED) and benign prostatic hyperplasia (BHP). Generic tadalafil became more widely available after What is Cialis? Cialis relaxes muscles of the blood vessels and increases blood flow to particular areas of the body. Cialis is used to treat erectile dysfunction (impotence) and symptoms of benign prostatic hypertrophy (enlarged prostate). CIALIS 20MG TABLET works by blocking the effects of certain enzymes (PDE5) in the body that limits blood flow to the penis. This relaxes the blood vessels supplying the penis, improves blood flow to the penis and makes it stay erect throughout the process of sexual intercourse.