Cream for erectile dysfunction is simply applied to the penis directly before sex. Erection creams for ED can be purchased OTC, though it is not recommended (or approved of) by the FDA. Talk to your doctor before incorporating any new medication regimen, including topical treatments like alprostadil cream. 8 Sources.These small differences affect the way each medication works, such as how quickly it takes effect and wears off, and the possible side effects. It lasts 4 to 5 hours, or longer if you have mild to moderate ED. These medications are potentially linked to fewer systemic side effects, especially for those with diabetes or heart disease. It works for up to 36 hours. However, these medications, such as Viagra, are not safe for all patients struggling with ED due to systemic side effects and drug-drug interactions two or more drugs reacting with one another. These medicines are called PDE5 inhibitors. Rarely reported side effects include: an erection that will not go away priapism.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 alcohol. Its effects often last for 4 to 5 hours. It might work longer if you have mild to moderate erectile dysfunction. Vardenafil. Erectile dysfunction affects an estimated 18 million men in the U.S. alone. Here you’ll find impotence information including its causes, impotence drugs, and other promising treatments for ED. Last updated on Uses Warnings Before taking Dosage Side effects Interactions FAQ What is sildenafil? Sildenafil relaxes muscles of the blood vessels and increases blood flow to particular areas of the body. Sildenafil under the name Viagra is used to treat erectile dysfunction (impotence) in men.They’re often the first line of treatment for trouble getting or keeping an erection, called erectile dysfunction ED. As well, the following populations should not use alprostadil cream: Known allergy to alprostadil. It might work longer if you have mild to moderate erectile dysfunction. If you prefer, you may contact the U. This medication is taken with or without food an hour before sex. Risks While Vitaros alprostadil cream is generally well-tolerated, a study did report users experiencing mild, short-lived side effects, including genital pain, tenderness, and skin redness.