The most common active ingredient in pills for erectile dysfunction is a class of active ingredients known as PDE- 5 inhibitors.

Viagra, Cialis and other newer ED drugs all use variations of PDE5 inhibitors to increase blood flow to the penis – the so called PDE 5 drugs.
 
PDE 5 inhibitors occur naturally in the herb horny goat weed found in natural ED supplements like Herbal Ignite and in some foods.

Herbal Products Multi-Functional
With the ED drugs their action is limited to one mechanism – increase blood flow – whereas herbal erectile treatments  work in a number of ways – like reducing stress, supporting nerve response, and lifting testosterone levels – as well as by increasing blood flow.

For more information on the importance of PDE 5 inhibitors and blood flow for erections see Bloodflow and Erections and the similarities of horny goat weed and PDE 5 drugs see Horny Goat Weed Treatment