to treat symptoms of bph, like needing to go frequently. tell your doctor about all your medical conditions and medicines, and ask if your heart is healthy enough for sex. do not take cialis if you take nitrates for chest pain, as it may cause an unsafe drop in blood pressure. do not drink alcohol in excess. side effects may include headache, upset stomach, delayed backache or muscle ache. to avoid long term injury, get medical help right away for an erection lasting more than four hours. if you have any sudden decrease or loss in hearing or vision, or any allergic reactions like rash, hives, swelling of the lips, tongue or throat, or difficulty breathing or swallowing, stop taking cialis and get medical help right away. ask your doctor about cialis for daily use and a free 30-tablet trial. tdd#: 1-800-345-255050 tjust waiting to be found. ties tdd#: 1-800-345-2550 at schwab, we're here to help