Does it work?

Can damiana act as an aphrodisiac?

BACKGROUND

Damiana is a small shrub, native to Mexico, that grows in various tropical and sub-tropical regions. Ancient Mayan tribes are reported to have used the herb as an aphrodisiac and hallucinogen. In the 1870s, damiana was widely promoted in the US as a patent medicine that would enhance sexual performance in both men and women. Interest soon faded, but the internet appears to have led to another revival in its use.

A small number of herbs are widely promoted to enhance love making. A review of these remedies in the Journal of Sex & Marital Therapynoted a significant increase in the use of such products. Damiana was the second most commonly used herb in products marketed to improve sexual performance. However, this review noted that promotional material was typically based on testimonials from pleased customers rather than the results of controlled studies.

The scientific name for the damiana plant is Turnera diffusa, although advertisements like to mention that the plant has also been known as Turnera aphrodisiaca. The plant contains a volatile oil that has an odour similar to chamomile. At least 35 different compounds have been identified in this oil, but none has been shown to act specifically as an aphrodisiac.

EVIDENCE FROM STUDIES

Laboratory tests on a few of the compounds isolated from damiana showed that they act similar to steroidal sex hormones. However, such steroids have complex actions that do not necessarily mean they will act as aphrodisiacs. A small number of studies have been published using an aqueous extract of damiana in male rats. In one test, rats that originally had little interest in sex became more interested after being fed damiana, and in another the rats given damiana engaged in sexual acts more frequently.

However, relating these results to humans is very difficult, especially given the complex psychological, emotional and relational dimensions of human sexuality.

Apart from anecdotal reports, no studies were found which examined the effect of damiana in men or women. Two small placebo-controlled studies are often mentioned in literature about damiana. In both, men and women reported higher sexual satisfaction when taking a herbal remedy containing damiana.

However, since the product contained three other herbs, along with several vitamins and minerals, it is impossible to determine whether or not damiana made a significant contribution to the effects.

PROBLEMATIC ASPECTS

The most common side effects from damiana are headaches and digestive complaints. The plant material contains what are called cyanogenic compounds. Similar materials are found in apple seeds and other natural materials.

This has raised concerns that damiana might cause cyanide-like toxicity. Such effects have not been reported, but it has been suggested that more than 200g of damiana plant material would need to be consumed to have any such adverse effects. One case has been reported in which someone consumed 200g of damiana and had tetanus-like convulsions.

RECOMMENDATIONS

The internet has been flooded by purveyors of quick and easy sexual satisfaction. Herbal remedies have been included among the products alleged to enhance sexual performance.

Although damiana has been used as an aphrodisiac for many decades – and longer – the long-time authority on herbal remedies, Prof Varro Tyler, researched this historical connection and concluded that it was a hoax. It took in the purveyors of patent medicines in the 19th century and appears to be having similar success today. The type of satisfaction being sought here is more likely to come from commitment and love, not herbal remedies.

Dónal OMathúna has a PhD in pharmacy, researching herbal remedies, and an MA in bioethics, and is a senior lecturer in the School of Nursing, Dublin City University