Taking more than 1 dose every 24 hours can cause heart issues and other problems. Talk to your doctor about which dosing schedule is right for you. If you are taking tadalafil to treat erectile dysfunction, follow your doctor’s directions and the guidelines in this paragraph. Physicians should discuss with patients the potential for CIALIS to augment the blood-pressure-lowering effect of alpha-blockers and antihypertensive medications. The decision of availability is completely up to the company marketing the product.Cialis is a popular ED medication. Find out everything you need to know about this doctor-prescribed medication including usage, effectiveness, and safety . Tadalafil (Cialis) is taken by mouth either as needed before sexual activity or once daily for erectile dysfunction (ED).It’s also taken once daily to treat symptoms from an enlarged prostate (benign prostatic hyperplasia, or BPH).Tadalafil (Cialis) is available both as brand-name and generic tablets. Common side effects of this medication include . Tadalafil (Cialis) is a medicine used to treat erectile dysfunction (ED, also called impotence) and problems with urination caused by an enlarged prostate (benign prostatic hypertrophy or BPH). Tadalafil works by helping to relax the blood vessels in the penis, allowing blood to flow into the penis, and causing an erection.