FDA encourages anyone aware of a serious side effect, including consumers or patients, to make a MedWatch report. Tell your doctor if any of these symptoms are severe or do not go away: headache. How will Cialis be supplied? Tadalafil Adcirca is used to improve the ability to exercise in people with pulmonary arterial hypertension PAH; high blood pressure in the vessels carrying blood to the lungs, causing shortness of breath, dizziness, and tiredness. The decision of availability is completely up to the company marketing the product. If you become pregnant while taking tadalafil, call your doctor.1. What is Cialis used to treat? Cialis is approved for the treatment of men who experience difficulty having and maintaining an erection (impotence). 2. How does Cialis work? . Tadalafil (Cialis) is used to treat erectile dysfunction (ED, impotence; inability to get or keep an erection), and the symptoms of benign prostatic hyperplasia (BPH; an enlarged . Cialis is a prescription medication containing the active ingredient tadalafil. Cialis belongs to a group of medications known as phosphodiesterase-5 (PDE-5) .