Viagra (sildenafil) and Cialis (tadalafil) are leading phosphodiesterase-5 (PDE5) inhibitors prescribed for erectile dysfunction (ED). Both enhance blood flow to the penis during sexual. Compare Viagra and Cialis to see how sildenafil and tadalafil differ in onset, duration, food effects, and dosing. Learn which ED medication may fit your lifestyle and how each PDE5 inhibitor works for erectile dysfunction. Viagra and Cialis are oral medications for treating erectile dysfunction. Check out side-by-side comparisons of these ED pills. A urologist's Viagra vs Cialis comparison: onset, duration, food effects, side effects, and which PDE5 inhibitor fits your sex life best. Which is better viagra or cialis? Cialis and Viagra are both PDE5 inhibitors used for the treatment of erectile dysfunction (ED). Both only work when a man is sexually aroused. Cialis lasts for around 36 hours compared with only 4 to 5 hours for Viagra. Compare Sildenafil vs Viagra head-to-head with other drugs for uses, ratings, cost, side effects and interactions. What’s the difference between Viagra and sildenafil? Discover more about these erectile dysfunction treatments and learn which might be best for your needs. Does Cialis work better than Viagra? Cialis and Viagra are usually considered equally effective. But Cialis tends to work for a longer period than Viagra, lasting up to 36 hours. Compare Viagra and Cialis side effects, costs and risks for treating Erectile Dysfunction. This article is written to clarify the medical facts behind the kamagra vs viagra discussion, using evidence, regulatory standards, and real clinical experience instead of marketing claims.