Wary of all the side-effects associated with popular penis popper pill Viagra, over-the-hill scientists tired of hearing “It happens to everyone. EXCEPT THE POST MAN” have begun to study new and exciting ways of making an old man bonery:

In the new study, Mario Dell’Agli and colleagues point out that Viagra (sildenafil) and several other prescription drugs are now available for ED, or male impotence. ED affects an estimated 18 million men in the United States alone. Studies show, however, that these drugs may cause side effects such as headache, facial flushing, stomach upset, and visual disturbances.

Also? Raging hard-ons that last for hours, making you see toilet paper rolls in a whole new light:

To find better treatments, the scientists studied herbal extracts reputed to improve sexual performance. Scientists exposed the substances to an enzyme that controls blood flow to the penis and whose inhibition results in an erection.

Of the extracts tested, “horny goat weed” was the most potent inhibitor of the enzyme. By chemical modification of icariin, the active ingredient purified from the extract, the scientists obtained a derivative with activity similar to Viagra and a potential for fewer side effects because it targeted the protein more precisely than sildenafil.

Anyone who has ever shopped at a small family-owned pharmacy, 99 cent store or bodega with your grandfather knows that, despite his attempt to distract you with an 87 cent “Barbee Doll,” already knows about the existence of Horny Goat Weed. And anyone who’s seen the satisfied look on that asshole post man knows it works. Your grandmother hasn’t been this happy since she had your-uncle-no-one-talks-about after a light-night romp in the jungles of Guantanamo with the fisherman’s son, Usmail.

Natural Viagra? ‘Horny Goat Weed’ Shows Promise [Science Daily]