Vardenafil's indications and contraindications are the same as with other PDE5 inhibitors; it is closely related in function to sildenafil citrate (Viagra) and tadalafil (Cialis). The difference between the vardenafil molecule and sildenafil citrate is a nitrogen atom's position and the change of sildenafil's piperazine ring methyl group to an ethyl group. Tadalafil is structurally different. Levitra (Vardenafil HCl) may treat, side effects, dosage, drug interactions, warnings, patient labeling, reviews, and related medications including drug comparison and health resources. Vardenafil (Levitra, Staxyn ODT) is a drug prescribed for the treatment of impotence (erectile dysfunction). Side effects, drug interactions, pregnancy information, dosing, and patient information should be reviewed prior to taking any medication. Find patient medical information for Vardenafil (Levitra, Staxyn) on WebMD including its uses, side effects and safety, interactions, pictures, warnings, and user ratings Vardenafil: side effects, dosage, interactions, FAQs, reviews. Used for: erectile dysfunction Description Vardenafil is used to treat men with erectile dysfunction (sexual impotence). It belongs to a group of medicines called phosphodiesterase 5 (PDE5) inhibitors. These medicines prevent an enzyme called phosphodiesterase type-5 from working too quickly. The penis is one of the areas where this enzyme works. Erectile dysfunction is a condition where the penis does not harden and expand. Vardenafil is used to treat erectile dysfunction (impotence; inability to get or keep an erection) in men. Vardenafil is in a class of medications called phosphodiesterase (PDE) inhibitors. It works by increasing blood flow to the penis during. Vardenafil is a medication that treats erectile dysfunction. ED is the inability to achieve and sustain an erection suitable for sexual intercourse. Levitra relaxes muscles and increases blood flow to particular areas of the body and is used to treat erectile dysfunction. Learn about side effects, interactions and indications. Vardenafil: learn about side effects, dosage, special precautions, and more on MedlinePlus.