Once a man has completed sexual activity, blood flow to his penis decreases, and his erection goes away. A phone or video consultation is sometimes required for legal purposes. Make sure to get an estimate of when you can expect your prescription in the mail. Some form of sexual stimulation is needed for an erection to happen with Levitra. Your primary care doctor should always know what medications you’re taking, including ED pills prescribed by another provider. The generic versions are just as effective and much less expensive.Levitra (vardenafil): This medication is taken one hour before sex and can last up to 24 hours. It’s available in 10 mg and 20 mg tablets. Stendra (avanafil): This is an as-needed medication taken 30 minutes before sex and can last up to six hours. It’s available in 50 mg, mg, and mg test1.rug: usa. Find patient medical information for Levitra oral on MD including its uses, side effects and safety, interactions, pictures, warnings and user test1.rug: usa. Vardenafil is the generic name of the drugs Levitra and Staxyn. It’s used to treat erectile dysfunction. Here’s how it test1.rug: usa.