Harvard Men's Health Watch

Viagra precautions

Q. I am a 64-year-old man. Aside from diabetes, I've been healthy and until now, the only prescription I've taken is insulin. But I've been having trouble with erections, and my doctor just gave me a prescription for Viagra. He also told me to be careful about using other drugs with Viagra but didn't give me a list. Can you please fill me in?

A. Viagra (sildenafil) is one of three widely used medications for erectile dysfunction; the others are Levitra (vardenafil) and Cialis (tadalafil). Although you'd never know it from their advertisements, the three medications are closely related and have similar — and very favorable — track records for effectiveness and safety. They also have similar drug interactions and require similar precautions.

To continue reading this article, you must login.
  • Research health conditions
  • Check your symptoms
  • Prepare for a doctor's visit or test
  • Find the best treatments and procedures for you
  • Explore options for better nutrition and exercise
Learn more about the many benefits and features of joining Harvard Health Online »