Lipoic acid (also known as alpha-lipoic acid, ALA) has been investigated for its potential use in treating heavy metal poisoning due to its antioxidant properties and ability to chelate certain metals. The rationale is based on its chemical structure, which allows it to bind metals such as mercury, arsenic, and cadmium, potentially facilitating their excretion from the body. In animal studies, ALA has demonstrated some efficacy in reducing organ damage and decreasing heavy metal concentrations in tissues. For example, studies in rats have shown that lipoic acid can mitigate the toxic effects of lead and mercury exposure, possibly by reducing oxidative stress and promoting renal elimination of these metals.

However, clinical evidence in humans is limited. A few small trials and case reports suggest that lipoic acid might have a supportive role when used alongside established chelation therapies, but it is not recognized as a primary chelator in standard medical practice. Most clinical guidelines for treating heavy metal poisoning recommend chelation agents with more robust evidence, such as dimercaprol, EDTA, or DMSA. Moreover, the ability of lipoic acid to cross cell membranes and the blood-brain barrier has led to speculation about its potential benefits, but definitive, large-scale human studies are lacking. As a result, while there is some scientific basis for its use, especially from preclinical studies, the overall clinical evidence remains weak (rated 2/5).