Educational information, not medical advice — ask your doctor or midwife.
Guayacán is the heartwood and resin of Guaiacum officinale, a slow-growing tropical tree. It grows in the Caribbean, Mexico, Central America and northern South America. The wood is also called lignum vitae, and it is one of the heaviest woods in the world.
In folk use it was taken as a wood tea or a resin tincture. The targets were joint pain, gout, rheumatic aches and skin eruptions. In the 1500s Europe also sold it as a cure for syphilis, which it is not.
Here is the honest verdict. There are no good human trials behind any of these uses. Long traditional use is not proof that a remedy works, and it is not proof that it is safe.
Short answer: no one has shown how guayacán works in people, or that it does anything.
Most of the chemistry sits in the resin, in compounds called lignans. In test tubes, some of these appear to slow inflammation signals and soak up free radicals. Whether that happens in a human joint is not known.
The old reasoning was different. Healers thought the wood made you sweat, and that sweating pushed illness out of the body. Sweating does not clear an infection.
Guaiac resin also turns blue when it meets blood. That is why old stool tests for hidden blood used it. It is a chemistry trick, not a sign of healing power.
Guayacán is usually sold as wood chips, a coarse powder, or an alcohol extract.
Common forms:
- Dried wood chips or shavings, simmered into a strong tea - Powdered wood in capsules - Tincture or fluid extract made from the resin - Raw guaiac resin lumps, sold by herb traders - Guaiac resin as a food additive (E314), used to keep fats fresh
One name warning matters here. In many shops "palo santo" means Bursera graveolens, a different tree sold as incense sticks.
Check the Latin name on the label before you buy. Strength is not standardised, so two brands of the same form can differ widely.
Taíno and other Caribbean peoples used the wood and resin before European contact. Spanish traders carried it to Europe in the early 1500s.
There it was sold as "holy wood" and promoted against syphilis. Wealthy patients paid large sums for it. The treatment failed, and the trade faded.
In Latin American folk practice, healers boiled the wood for gout, joint pain and skin complaints. European pharmacy books kept it for rheumatism into the 1900s. Germany's Commission E later listed the wood as a supportive measure for rheumatic aches.
Stop taking it and see a doctor if you get any of these:
- A rash, swelling of the lips or face, or trouble breathing - Severe belly pain, vomiting blood, or black tarry stools - Yellow skin or eyes, or dark urine - Joint pain that keeps getting worse, or a hot swollen joint with fever
Call emergency services for swelling of the throat or breathing trouble. Those can be signs of a serious allergic reaction.
Guaiacum officinale is listed on CITES Appendix II, so international trade in the wood is controlled. In the United States it is sold as a dietary supplement, with no official approval to treat any illness. In the EU and UK, guaiac resin is allowed as a food antioxidant (E314).
Evidence grades and traditional-use labels are explained in our methodology. Nothing here is medical advice.
What it is typically used for, usual dose, cautions, and the study behind it where real trial data exists.
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