Tadalafil is generally safe for most men with ED. However, men who have other health conditions should alert their doctor prior to starting any erectile dysfunction medication.
Some medical conditions and symptoms that may predispose someone to adverse effects from tadalafil include heart problems like heart failure or a previous heart attack, angina or chest pain, irregular heartbeats, high or low blood pressure, retinitis pigmentosa (a rare genetic eye disease), pulmonary hypertension, stroke, liver disease, kidney disease, severe vision loss, stomach ulcers, bleeding problems, deformed penis shape or Peyronie's disease, experience with erections lasting more than 4 hours, or blood cell disorders like sickle cell anemia, multiple myeloma, or leukemia.