Cialis is a prescription medicine used to treat impotence, known medically as erectile dysfunction (ED) and symptoms of enlarged prostate (benign prostatic hyperplasia, or BPH).
Cialis is in a group of medications called phosphodiesterase 5 (PDE5) inhibitors. It works by increasing blood flow to the penis during sexual stimulation. It may also relax the prostate and bladder.
Cialis comes in tablet form and is either taken one time before you expect to have sexual activity, or at a lower dose, once daily.
Common side effects include headache, indigestion, back pain, and facial flushing. Do not take Cialis if you are taking other medications called "nitrates."
