What is muira puama?

Muira puama is a small tree from the Amazon rainforest of Brazil. Herbalists use the dried wood and root, cut into chips or ground to powder. The trade name "potency wood" comes from its old use for sexual complaints.

People buy it today for low sex drive, erection trouble, tiredness and low mood. In Latin American folk practice it was also treated as a tonic for the nerves. It is sold on its own and in blends with herbs like catuaba and guarana.

Here is the honest verdict. Human evidence is very thin, and the few studies in people had no comparison group. Most of the rest comes from lab dishes and from rats.

A long record of traditional use does not prove that a remedy works. It does not prove that it is safe either. Both have to be shown separately, and for this plant neither has been.

How does muira puama work?

No one has shown how muira puama works in the human body. The ideas below come from lab and animal studies only.

In test tube work, extracts slow an enzyme called acetylcholinesterase (it breaks down a brain signalling chemical). Some memory drugs act on that same enzyme. Whether the herb does this in a living human brain is unknown.

In aged rats, extracts cut signs of oxidative stress (a kind of cell damage) in brain tissue. In mouse mood tests, extracts acted a little like an antidepressant. Animal results often fail to carry over to people.

No study has shown how it might affect sex drive, arousal or erections. The traditional idea was that the wood warms and strengthens the body. That is a folk explanation, not a tested mechanism.

Some sellers claim it raises testosterone. Human trials have not tested that claim.

What forms does muira puama come in?

Muira puama is sold in a few common forms:

- Dried wood chips and shavings, simmered in water - Capsules and tablets of powdered wood or root - Alcohol tinctures and liquid extracts - Concentrated dry extracts, often labelled 4:1 or 10:1

Many of the plant's compounds do not dissolve well in plain water. Traditional practice used alcohol or a long simmer for that reason.

Products vary a lot in strength. Labels often do not say which plant part was used. Some blends mix it with other herbs, which makes side effects harder to trace.

Supplements are not tested before sale in most countries. Choosing a brand that pays for outside lab testing is one way to lower the risk of a mislabelled product.

Where it comes from:

Muira puama has a long record of use in the Amazon basin. Indigenous groups in Brazil used the wood and root as a general tonic. Decoctions were taken for tiredness and for sexual complaints.

European interest began in the 1800s. The wood was shipped out and listed in British herbal texts as "potency wood". It was later sold in France as a nerve tonic.

Brazilian folk practice also used it for joint pain, upset stomach and period pain. Some healers rubbed the soaked wood on sore limbs.

These uses were written down by travellers, traders and herbalists. They were not tested in controlled studies at the time. The record tells you what people did, not what it did for them.

What does muira puama help with?

• Low sex drive in men and women: This is the main reason people buy muira puama. Tradition in Brazil treated it as a sexual tonic for both sexes. The human evidence is weak. Open studies in the 1990s asked men and women to rate their desire after taking it. Many reported gains, but there was no placebo group, so the result may be expectation. No modern randomised trial has tested it. It has not been shown to raise sex drive.
• Erection problems: Tradition used the wood for male "potency". That is where the trade name came from. The only human reports are uncontrolled. Men chose to take it and then rated themselves, which is the weakest kind of evidence. Erection trouble can be an early sign of heart disease or diabetes. Get it checked rather than self-treating it.
• Everyday tiredness and low energy: Folk use treated the wood as a tonic for people worn down by work or illness. Some users describe a mild lift. No trial has measured energy or stamina in people taking it. Ongoing tiredness has many medical causes, including low iron and thyroid problems. Those need testing, not a supplement.
• Low mood: In mouse mood tests, extracts behaved a little like an antidepressant. That finding is from animals. No human trial has tested it for depression or anxiety. There is no basis for using it in place of care. If your mood has been low for weeks, speak to a doctor.
• Memory and focus complaints: In test tube work, extracts slow an enzyme that breaks down a brain signalling chemical. Aged rats also did better on memory tasks in some studies. No human memory trial has been published for the herb alone. One open study paired it with ginkgo, which clouds what did what. Memory loss in an older adult needs a medical assessment.
• Period pain: Brazilian folk practice used decoctions for cramps and stomach upset. There is no human research on this use at all. Any benefit is unknown. Severe or worsening period pain deserves a medical check.

What are the side effects of muira puama?

• Stomach upset or nausea
• Headache
• Trouble falling asleep
• Restlessness or jitteriness
• Feeling your heart beat faster
• Alcohol effects from tinctures, which can be strong

Good to know:

Reported side effects are mild and uncommon in the small studies that exist.

That is weak reassurance. The studies were short, small and poorly controlled, so rare or slow-building harms would have been missed.

Stop taking it and get medical advice if you feel unwell after starting it.

How much muira puama should you take?

• Recommended daily: There is no dose shown to be safe or useful in people. What follows is simply what labels carry. Capsule labels for powdered wood commonly list 500 mg to 1,500 mg a day. Tincture labels often list a few millilitres a day, split into doses. Concentrated 4:1 extracts list smaller amounts. These are label figures, not guidance for you. Products differ in strength, so the same number of milligrams means different things across brands.
• Best time of day: Timing has not been studied, so it likely does not matter much. Some users find it mildly stirring. If that is you, a late dose may disturb sleep.
• With or without food: Either is fine. Taking it with food may ease stomach upset, which is a common complaint. Alcohol tinctures are usually stirred into water or juice first.
• Time to effect: Honestly, it may do nothing at all. Sellers often say two to four weeks. That figure comes from marketing, not from trials. Any quick lift you feel could be placebo, and with tinctures it could be the alcohol.
• How long to take it: Most labels suggest short runs of a few weeks. No study has followed people taking it for months or years. Long-term safety is simply unknown. If you are using it and nothing has changed after a few weeks, there is no reason to keep going.