Abstract: The reduced or “leuco” forms of certain pharmaceutical compounds can be produced and/or stabilised by mixing the unreduced compounds or the reduced compounds, respectively, with acid and a sulphydryl compound, especially a sulphur-containing amino acid, or peptide or derivative of such an amino acid.

Abstract: The reduced (or ‘leuco’) forms of certain pharmaceutically active compounds can be used for the treatment or pro-phylaxis methaemoglobinaemia or of a disease or disorder associated with or resulting from oxidative stress, such as Alzheimer's disease, motor neurone disease, Lewy Body disease, Pick's disease, Progressive Supranuclear Palsy, ischaemia, myocardial infarction, acute lung injury, stroke, Parkinson's disease or haemolysis and anaemia in acute falciparum malaria.