Before taking tadalafil, tell your doctor and pharmacist if you are allergic to tadalafil, any other medications, or any of the ingredients in tadalafil tablets. In , Pfizer scientists discovered that sildenafil, which also inhibits the PDE5 enzyme, caused penile erection in males participating in a clinical study of a heart medicine. CIALIS for Use as Needed for ED In eight primary placebo-controlled clinical studies of 12 weeks duration, mean age was 59 years range 22 to 88 and the discontinuation rate due to adverse events in patients treated with tadalafil 10 or 20 mg was 3. If you are taking tadalafil to treat erectile dysfunction, you should know that it does not cure erectile dysfunction or increase sexual desire. Also tell your doctor if you have or have ever had pulmonary veno-occlusive disease PVOD; blockage of veins in the lungs ; any condition that affects the shape of the penis; diabetes; high cholesterol; high or low blood pressure; irregular heartbeat; a heart attack or heart failure; angina chest pain ; a stroke; ulcers in the stomach; a bleeding disorder; blood circulation problems; blood cell problems such as sickle cell anemia a disease of the red blood cells , multiple myeloma cancer of the plasma cells , or leukemia cancer of the white blood cells ; or heart, kidney, or liver disease. Ask your pharmacist or doctor for a copy of the manufacturer’s information for the patient. 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.Cialis is a very popular and potent impotence treatment, based on the active ingredient tadalafil. / 5. Blanca Johnston. The majority of men will at some point struggle with attaining and maintaining aThe biggest difference between Viagra and Cialis is how long the drugs last in your system. The most commonly reported side effects in patients treated with Cialis during the testing of the product were: headache. indigestion. back pain. muscle pain. flushing. stuffy nose. Patients who. 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.