Can Cialis be used with other treatments for impotence? If you are thinking about using tadalafil please discuss it with your doctor. 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. Side effects Side effects of oral ED medicines are often mild. It affects the way the medicine works. Severe liver disease. Do not stop taking tadalafil without talking to your doctor.Tadalafil is a generic version of the prescription drug Cialis. Doctors prescribe it to treat . Tadalafil is in a class of drugs called phosphodiesterase-5 (PDE5) inhibitors and is . Cialis is used to treat erectile dysfunction (impotence) and symptoms of benign prostatic .