Levitra contains the active ingredient vardenafil, while Viagra contains sildenafil. They are both phosphodiesterase type 5 inhibitors prescribed to manage erectile dysfunction.
Levitra should be taken as needed about an hour before sexual activity. It should last about 4 to 5 hours. It can be taken with or without food. The most common side effects from Levitra are flushing and headache.
Viagra should be taken as needed and can be taken 30 minutes to 4 hours before sexual activity. If taken with a high-fat meal, Viagra may take longer to work. The most common side effects of Viagra include flushing, diarrhea, indigestion, headache, back pain, limb pain, muscle pain, and vision changes. The ability to produce an erection with Viagra usually lasts at least 4 hours.
