Many people add herbs like Horny Goat Weed (HGW) to Viagra or other ED drugs to improve the effect of these drugs. Is that a good idea? New research suggest that you shouldn’t do that.

In the past, I thought why not? I advocated using the traditional Chinese herb Epimedium (Horny Goat Weed) + Viagra (or similar drugs Cialis or Levitra). However, here is a study from China which says that combining HGW + Viagra (sildenafil) LOWERS levels of Viagra (which is a bad thing, because you get less active drug).

Here’s the information:

Abstract

Epimedium sagittatum (Sieb. et Zucc.) Maxim is one of the herbs used to treat erectile dysfunction in Traditional Chinese Medicine. Sildenafil is a phosphodiesterase 5 inhibitor used to treat erectile dysfunction in Western Medicine. This study evaluates the herbal-drug interaction of Epimedium sagittatum extract on the pharmacokinetics of sildenafil in rats by ultra-performance liquid chromatography. The rat plasma was sampled from each anesthetized rat after pretreatment with 3-daysEpimedium sagittatum extract (1/2 g/kg/day) and intravenous injection with sildenafil (10/30 mg/kg). The pharmacokinetic data demonstrate that the area under the concentration-time curve (AUC) of sildenafil (10 mg/kg) was significantly decreased in groups that received a high dose of Epimedium sagittatum extract. In conclusion, the study demonstrates that there was significant herb-drug interaction of Epimedium sagittatum extract on the pharmacokinetics of sildenafil at low and high daily doses, suggesting co-administration use of Epimedium sagittatum extract and sildenafil in clinical practice should be prevented due to possible herb-drug interactions.

Here is a link to the article, which includes a full-text PDF for free:

http://www.mdpi.com/1420-3049/18/6/7323

I am not familiar with the journal (Molecules) and can’t vouch for the research but I think it’s worth considering.