The products discussed in this site may have different product labeling in different countries. If you have an erection that lasts more than 4 hours, get medical help right away. Its effects often last for 4 to 5 hours. The body takes longer to absorb it after a high-fat meal or alcohol. A newer form of the medicine that dissolves on the tongue might work faster than the pill that you swallow.CHOOSE BRAND-NAME VIAGRA The original little blue pill prescribed by doctors for over 20 years Clinically proven to treat men with erectile dysfunction (ED) Ongoing . Cost Overdose Ask your doctor Q&A Drug Images What is Viagra? If you have erectile dysfunction (ED), your doctor may recommend that you take Viagra. It’s a . Sildenafil (Viagra). This medicine works best when you take it on an empty stomach an hour before sex. The body takes longer to absorb it after a high-fat meal or .