It aids in decreasing the blood pressure in your lungs. Prolonged erections can be dangerous. Tadalafil belongs to a group of medicines called phosphodiesterase 5 PDE5 inhibitors. Communicate with your partner and interact with them after you take Cialis to help the medication work. For CIALIS for use as needed, over and subjects were treated for at least 6 months and 1 year, respectively. This is high blood pressure that occurs in the main artery that carries blood from the right side of the heart the ventricle to the lungs. Individuals with “crowded” optic disc are also considered at greater risk for NAION compared to the general population; however, evidence is insufficient to support screening of prospective users of PDE5 inhibitors, including CIALIS, for this uncommon condition.CIALIS for once daily use is a lower dose you take every day. • Do not take CIALIS more than one time each day. • Take one CIALIS tablet every day at about the same time of day. You may attempt sexual activity at any time between doses. • If you miss a dose, you may take it when you remember but do not take more than one dose per day. Cialis is a medication approved by the Food and Drug Administration (FDA) often used to treat erectile dysfunction (ED) and benign prostatic hyperplasia (BPH) in . Tadalafil Brand names: Cialis, Adcirca. Tadalafil. Find out how tadalafil treats erectile dysfunction, pulmonary hypertension and benign prostate enlargement, and how to take it.