German researchers have reported promising results from a clinical trial of an herbal supplement that might alleviate impotence and low libido problems.

Citing German media sources, the medical news website Theonlineclinic.com reports the tested remedy contains a mix of herbal products, including Tribulus terrestris, which is already used in a variety of alternative medicines, maca, a root vegetable found in the Andes, and grape juice extract.

The mix of ingredients is believed to increase testosterone levels and enhance blood flow.

Preliminary results have shown men taking the supplement experienced better sex and a higher libido than the control group taking Viagra.

Olaf Shroeder from Charite hospital in Berlin, who led the clinical trials, told German daily newspaper Sueddeutsche Zeitung,”Men had much better sex afterwards, more fun in bed and generally felt much better about themselves,” quoted by the website.

German media have also reported that further trials are scheduled to take place later in the year, and the remedy may become available as early as 2010.