If you become pregnant while taking tadalafil, call your doctor. Obesity Additionally, certain risk factors increase the risk of ED, such as smoking , lack of exercise, and drug or alcohol use. Ask your pharmacist or doctor for a copy of the manufacturer’s information for the patient. The maximum recommended dosing frequency is once per day in most patients. Also tell your doctor if you or any of your family members have or have ever had an eye disease such as retinitis pigmentosa an inherited eye condition that causes loss of vision or if you have ever had sudden severe vision loss, especially if you were told that the vision loss was caused by a blockage of blood flow to the nerves that help you see. This is a serious condition that requires immediate medical attention. Your doctor will help you decide the best time for you to take tadalafil before sexual activity.Tadalafil, sold under the brand name Cialis among others, is a medication used to treat erectile dysfunction, benign prostatic hyperplasia, and pulmonary arterial hypertension. Tadalafil is an annulated 2,5-diketopiperazine. It is also a 1,2,3,4-tetrahydro-β-carboline. stockcam / Getty Images What is generic Cialis? Generic Cialis is called tadalafil, which is the active ingredient in Cialis. Cialis is Food and Drug Administration (FDA) approved to treat. Tadalafil is used to treat the symptoms of two conditions found in men: benign prostatic hyperplasia (BPH) and erectile dysfunction (ED). Tadalafil is also used to treat pulmonary arterial.