Dichloroacetic acid, often abbreviated DCA, is the chemical compound with formula CHCl2COOH. It is an acid, an analogue of acetic acid, in which two of the three hydrogen atoms of the methyl group have been replaced by chlorine atoms.
The salts and esters of dichloroacetic acid are called dichloroacetates. Salts of DCA have been studied as potential drugs because they inhibit the enzyme pyruvate dehydrogenase kinase.
Cancer cells change the way they metabolize oxygen in a way that promotes their survival. In laboratory studies of isolated cancer cells grown in tissue culture, DCA restores the original metabolism, and promotes their self-destruction. This has led to the use of DCA for treating cancer, by individuals experimenting with it themselves, by doctors administering it to patients as a non-approved drug, by scientists testing it in cancer tissue cultures in cell culture and in mice, and in human Phase II studies. DCA has improved certain biochemical parameters, but it has not demonstrated improved survival.