Erectile Dysfunction also more commonly termed impotence is the inability to achieve or sustain a penile erection. Three most viable drugs for Impotence are Viagra, Cialis and Levitra.

Viagra, first FDA approved treatment for erectile dysfunction, has been manufactured by pharmaceutical giant Pfizer. It blocks an enzyme called Phosphodiesterase Type 5 (PDE-5) which makes blood to flow out of penis. Increased blood retention and blood flow in penis helps men achieve better erection. Click here to buy Viagra online.

Cialis, although similar to Viagra in functionality, starts working within half an hour and lasts upto 36 hours. You can buy Cialis in dosage of 5mg, 10mg or 20mg .In contrast Viagra is available in dosages og 25mg, 50mg and 100mg.

As is the case with Viagra and Cialis, Levitra works by reducing blood flow out of the penis. Levitra starts producing effect within 1 hour and results last upto 4 hours. Clinical studies have shown Levitra to be approximately 80% effective.

All of above impotence drugs are prescription only treatments having their own side effects and should be taken only after proper consultation and guidance of legal medical practitioner to avoid any future health risks.