Is It Safe to Take Cialis Daily? Unlike other ED medications, such as Viagra® (sildenafil) and Levitra® (vardenafil), which work for four to five hours per dose, Cialis® (which contains the active ...

Like Viagra, Stendra and Levitra, Cialis is highly effective as a treatment for ED. But no medication has a 100 percent success rate, and Cialis is no exception. Even after you take Cialis, you could ...