Tell your doctor if tadalafil is not working well or if you are experiencing side effects. If you are taking tadalafil on a regular schedule, take it at around the same time every day. 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. Do not use in larger or smaller amounts or for longer than recommended. Your doctor may need to change the doses of your medications or monitor you carefully for side effects. Tell your doctor if any of these symptoms are severe or do not go away: headache. If you have certain health conditions or are taking certain medications, your doctor may tell you to take tadalafil less often or may prescribe a lower dose to be taken once a day.Not typically. The maximum recommended dosage of Cialis is 20 milligrams (mg) once daily if you take it as needed to treat erectile dysfunction (ED). For all other . 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 (tadalafil) is prescribed to treat erectile dysfunction and symptoms of benign prostatic hyperplasia. It comes as a tablet that’s taken as needed or once per .