Oral medicines for ED usually work well and cause few side effects. This medicine works best when you take it on an empty stomach an hour before sex. Keep from freezing. It lasts 4 to 5 hours, or longer if you have mild to moderate ED. Storage Store the medicine in a closed container at room temperature, away from heat, moisture, and direct light. An inherited eye disease that affects the retina.As a walk-in clinic, we treat patients on a first-come, first-served basis. Once you register, the kiosk will display your approximate wait time. You can be sure you get the same . Don’t be fooled into buying “herbal viagra.” Never take any medicines that claim to be the “herbal” or nonprescription version of an oral medicine for ED. These aren’t an effective . These lists contain up to 10 of the most common mild side effects that can occur with Viagra, with Levitra, or with both drugs (when taken individually). Can occur with Viagra: .