We've all gotten the emails advertising for cheaper prescription drugs. Some people have tried these cheaper drugs. But now researchers are warning us that Viagra bought on the internet may not be safe.

About half of tghe Viagra sold online is not actually made by Pfizer, the company that makes Viagra. The fake Viagra may be harmful to your health and may even cause heatrt attacks.

Scientist and doctors are warning Viagra users to avoid buying Viagra online.