Cialis As Needed will be prescribed in doses of 5 to 20 mg. Clinicians recommend taking them on an empty stomach. Because patients with recent heart attacks or stroke, heart pains angina , heart failure, uncontrolled blood pressure or uncontrolled irregular heart beats, severe liver disease, and retinal eye problems were not studied with Cialis, Cialis is not recommended for these patients. What if I am taking other drugs? Knowledge is Power It’s imperative to consult a healthcare professional before starting any medication, including Cialis. Patients who have a condition called “left ventricular outlet obstruction” from valvular problems or heart muscle enlargement may get side effects such as fainting or light-headedness. Some might experience headaches, back pain, or flushed skin.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 . Cialis (tadalafil) is an expensive drug used to treat erection problems in men. It may also be used to treat the enlargement of the prostate gland. This drug is slightly more popular . 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.