D-lactic acid

D-lactate is a form of lactic acid produced by bacteria such as Enterococcus and Streptococcus. It is an indicator of bacterial overgrowth in the gastrointestinal tract. It produced by bacteria in the colon when carbohydrates are not completely absorbed in the small intestine, such as in the case of patients who have had surgical resection of the bowel. In large quantities it can lead to d-lactic acidosis.

D-lactate is different from L-lactate in that it cannot be metabolized by humans and must be excreted through the kidneys. It can produce a variety of neurological symptoms including dysarthria and ataxia and is elevated in chronic fatigue syndrome.