A phosphodiesterase-5 (PDE5) inhibitor, Levitra was introduced to the market in 2003, around the same time as Viagra and Cialis. It enhances blood flow to the penis during sexual stimulation by inhibiting the PDE5 enzyme normally responsible for regulating, or limiting, that blood flow. Also known by the name of https://answers.launchpad.net/ubuntu/+source/deal/+question/682181