Muira puama, also called “potency wood,” is a small tree that grows to 5 m high and is native to the Brazilian Amazon and other parts of the Amazon rainforest. The small, white flowers have a pungent fragrance similar to jasmine’s. The Ptychopetalum genus is a small one—only two species of small trees grow in tropical South America and five in tropical Africa. The two South American varieties, P. olacoides (found in Brazil, French Guiana, Guyana, and Suriname) and P. uncinatum (found only in Brazil), are used interchangeably in South American herbal medicine systems. The olacoides variety is usually preferred, as it has a higher content of lupeol (one of the plant’s active phytochemicals). A completely different species of Brazilian tree, Liriosma ovata, also goes by the common name of muira puama (and is often sold in commerce as such); however, it is a completely different tree with a different phytochemical makeup.

Historically, all parts of muira puama have been used medicinally, but the bark and roots are the most-utilized parts of the plant. It has long been used in the Amazon by indigenous peoples for a number of purposes. Native peoples along the Brazilian Amazon’s Rio Negro use the stems and roots from young plants as a tonic to treat neuromuscular problems; a root decoction is used in baths and massages for treating paralysis and beri-beri; and a root-and-bark tea is taken to treat sexual debility, rheumatism, grippe, and cardiac and gastrointestinal asthenia. It’s also valued there as a preventive for baldness. In Brazilian herbal medicine, muira puama still is a highly-regarded sexual stimulant with a reputation as a powerful aphrodisiac. It has been in the Brazilian Pharmacopoeia since the 1950s. It is used as a neuromuscular tonic for asthenia and paralysis, dyspepsia, menstrual disturbances, chronic rheumatism (applied topically), sexual impotence, grippe, ataxia, and central nervous system disorders.

Muira puama is employed around the world today in herbal medicine. Early European explorers noted the indigenous uses and the aphrodisiac qualities of muira puama and brought it back to Europe, where it has become part of herbal medicine in England. It is still listed in the British Herbal Pharmacopoeia (a noted herbal medicine source from the British Herbal Medicine Association); it is recommended there for the treatment of dysentery and impotence. It is also used in Europe to treat impotence, infertility, neurasthenia, menstrual disturbances, and dysentery. In Germany, muira puama is employed as a central nervous system tonic, for hookworms, menstrual disturbances, and rheumatism. Muira puama has been gaining in popularity in the United States, where herbalists and health care practitioners are using it for impotence, depression, menstrual cramps and PMS, neurasthenia, and central nervous system disorders.

Scientists began searching for the source of muira puama’s efficacy in the 1920s. Early researchers discovered that the root and bark were rich in fatty acids and fatty acid esters (the main one being behenic acid), essential oils (including beta-caryophyllene and alpha-humulene), plant sterols, triterpenes (including lupeol), and a new alkaloid—which they named muirapuamine. Scientists resumed researching the plant’s constituents and pharmacological properties in the late 1960s and continued into the late 1980s. These studies indicated that the active constituents also included free long-chain fatty acids, sesquiterpenes, monoterpenes, and novel alkaloids.

In one of the early studies, researchers indicated that muira puama was effective in treating disorders of the nervous system and sexual impotence, and that “permanent effect is produced in locomotor ataxia, neuralgias of long standing, chronic rheumatism, and partial paralysis.” In 1930, Meiro Penna wrote about muira puama in his book Notas Sobre Plantas Brasilerias. He cited physiological and therapeutic experiments conducted in France by Dr. Rebourgeon that confirmed the efficacy of the plant for “gastrointestinal and circulatory asthenia and impotency of the genital organs.”

The benefits of treating impotence with muira puama have been studied in two human trials in France, which reported that muira puama was effective in improving libido and treating erectile dysfunction. In a Paris, France, study among 262 male patients who experienced lack of sexual desire and the inability to attain or maintain an erection, 62% of the patients with loss of libido reported that the extract of muira puama “had a dynamic effect,” and 51% of patients with erectile dysfunction felt that muira puama was beneficial. The second study evaluated positive psychological benefits of muira puama in 100 men with male sexual asthenia. The therapeutic dosage was 1.5 g of a muira puama extract daily. In their final report, researchers indicated muira puama could “enhance libido [in 85% of the test group], increase the frequency of intercourse [in 100 %] and improve the ability to maintain an erection [in 90%].”

In other recent clinical research, muira puama extracts have been reported to have in vivo adaptogenic, antifatigue, antistress, and CNS effects in humans and animals. A specially-prepared extract from the root of muira puama has been patented for its ability to “relieve physical and mental fatigue” and for “ameliorating a weakened constitution.” Researchers in Brazil documented a definite CNS effect of the bark in studies with mice. The bark of muira puama also has demonstrated a mild, short-lived, hypotensive effect. The root was found to inhibit stress-induced ulcers, while the leaf demonstrated an analgesic effect. Another U.S. patent has been filed on muira puama, citing that it can “reduce body fat percentage, increase lean muscle mass and lower cholesterol” in humans and animals with long-term use (and with no toxicity noted). Toxicity studies with mice (published in 1983) also indicated no toxic effects (at dosages of 50mg/kg, in an ethanol extract).

While so-called aphrodisiacs have come and gone in history, muira puama has retained its stature and may well provide one of the more effective natural therapeutic approaches for erectile function and libido enhancement. Before trying to self-treat, however, men should always seek the advice of a health practitioner (if erectile dysfunction or impotency is a problem); this often can be an early warning of vascular insufficiency and/or heart conditions.

To achieve the libido and potency effects of this particular plant, proper preparation methods must be employed. The active constituents thought to be responsible for muira puama’s potency and libido effect are not soluble in water—taking bark or root powder in capsules or tablets will not be very effective. High heat for at least 20 minutes with alcohol is necessary to free the volatile and essential oils, terpenes, gums, and resins found in the bark and root which have been linked to muira puama’s beneficial effects.

Traditional Remedy: Since many of the most active principals are not water soluble it is best to prepared this plant as a tincture, using 1–3 ml of a 4:1 tincture twice daily. Boiling the tincture for 20 minutes will help facilitate extraction of the non-water-soluble chemicals. For its tonic effect, one of the traditional remedies is to gently simmer 1 teaspoon of root and/or bark in one cup of water for 15 minutes and take 1/3 to 1 cup daily.