Tadalafil is not usually used to treat benign prostate enlargement because there is not enough evidence about how well it works. Subsequently, the FDA approved both vardenafil [27] and tadalafil in What side effects can this medication cause? You can only get it on prescription for erectile dysfunction if you have a specific condition such as multiple sclerosis or a spinal cord injury. Therefore the use of such treatments in combination with Cialis is not recommended.About tadalafil Brand names: Cialis, Adcirca. About tadalafil. Tadalafil is a medicine used to treat erection problems (erectile dysfunction) and symptoms of an enlarged prostate (benign prostate enlargement). It’s also sometimes used to treat pulmonary hypertension (high blood pressure in the blood vessels that supply the lungs). A manufacturer coupon or copay card is not available for Cialis. However, GoodRx discounts are available to help make it more affordable. Tadalafil, the generic version of Cialis is available for about $9 for 30 tablets of the 5 mg strength. headache. indigestion. back pain. muscle pain. flushing. stuffy nose. Patients who get back pain and muscle aches usually get them 12 to 24 hours after taking Cialis and these usually go away by.