Cialis Generic Name: tadalafil (ta DAL a fil) Brand Names: Cialis What is Cialis? Cialis (tadalafil) relaxes muscles and increases blood flow to particular areas of the body. Cialis is used to treat erectile dysfunction (impotence) in men. Cialis is also used to treat the signs and symptoms of benign prostatic hyperplasia (BPH), a condition in which the prostate gland becomes enlarged. Adcirca, another brand of tadalafil, is used to treat pulmonary arterial hypertension and improve exercise capacity in men and women. Cialis may also be used for purposes other than those listed in this medication guide. How should I take Cialis? Take Cialis exactly as prescribed by your doctor. Do not take in larger or smaller amounts or for longer than recommended. Follow the directions on your prescription label. Cialis can be taken with or without food. Do not break or split a Cialis tablet. Swallow it whole. Cialis is usually taken only once per day. Follow your doctor's instructions. For erectile dysfunction, take the medicine just before sexual activity but not more than once per day. Cialis can help achieve an erection when sexual stimulation occurs. An erection will not occur just by taking a pill. Follow your doctor's instructions. Do not take Cialis for erectile dysfunction if you are taking Adcirca for pulmonary arterial hypertension. Do not take Cialis more than once a day. Allow 24 hours to pass between doses. If you take the medication daily, take it at the same time each day. Store Cialis at room temperature away from moisture and heat. What happens if I miss a dose? Since Cialis is used as needed, you are not likely to be on a dosing schedule. If you take tadalafil every day and you miss a dose, take the missed dose as soon as you remember. Skip the missed dose if it is almost time for your next scheduled dose. Do not take extra medicine to make up the missed dose. What happens if I overdose? Seek emergency medical attention. Overdose symptoms may include chest pain, nausea, irregular heartbeat, and feeling light-headed or fainting. What should I avoid while taking Cialis? Drinking alcohol can increase certain side effects of Cialis. Grapefruit and grapefruit juice may interact with Cialis and lead to potentially dangerous effects. Discuss the use of grapefruit products with your doctor. Avoid using other medicines to treat erectile dysfunction, such as sildenafil (Viagra) or vardenafil (Levitra) while you are taking Cialis. General information: If you have any questions about Cialis, please talk with your doctor, pharmacist, or other health care provider. Cialis is to be used only by the patient for whom it is prescribed. Do not share it with other people. If your symptoms do not improve or if they become worse, check with your doctor. Check with your pharmacist about how to dispose of unused medicine.