Side Effects Of Muira Powder

Muira powder is made from the dried bark and roots of a Brazilian species of tree called Ptychopetalum olacoides, also known as muira puama or "potency wood." As the latter nickname implies, this herb is traditionally used to treat sexual disorders. However, it is also used to treat rheumatism, anxiety, depression, diarrhea, fatigue and loss of appetite. Muira powder may produce unwanted side effects and drug interactions, so check with your doctor before using it.

Insomnia

Athletes sometimes use muira puama because the herb is reputed to enhance endurance and performance. According to the results of a study published in the May 16, 2002, issue of "Phytotherapy Research", the stimulatory effects on the central nervous system provided by this herb are comparable to pentylenetetrazol, a drug once used to stimulate the respiratory and circulatory systems. (Reference 1) While this effect may increase short-term energy and alertness, it can also cause insomnia and restlessness in some individuals.

Seizures

Another similarity between compounds found in muira puama and the drug pentylenetetrazol is that they are both GABA-A receptor antagonists. This means that gamma-aminobutyric acid is suppressed, a neurotransmitter that contributes to the regulation of brain wave activity, muscle coordination and glandular functions. However, according to an article in the February 25, 2007, issue of Scientific American, GABA inhibition may trigger seizure activity. (Reference 2) In fact, this is why the U.S. Federal Drug Administration eventually banned pentylenetetrazol. Since muira puama also inhibits GABA-A, this herb should not be used if you have a history of epilepsy or are taking anti-seizure medications.

Stomach Upset

According to the "Physicians' Desk Reference for Herbal Medicines," muira puama also inhibits acetylcholinesterase, which may interfere with the digestion of food and produce stomach upset and nausea. (Reference 3) In addition, the PDR says that this herb also contains beta sitosterol, which the database at Drugs.com cautions may decrease intestinal absorption of vitamin E and carotenes. (Reference 4) If you have a history of gastrointestinal disorders, such as peptic ulcers, talk to your doctor about these side effects before using this herb.

Drug Interactions

Another paper published in Phytotherapy Research on April 23, 2009, reported that muira puama appears to alter levels of dopamine and serotonin in the brain, which may explain why this herb is traditionally used as a natural antidepressant. (Reference 5) While this may be a positive benefit, the antidepressant activity of the herb also indicates that it should not be used in conjunction with antidepressant medications.