The invention relates to nitisinone (2-[2-nitro-4-(trifluoromethyl)benzoyl]-1,3-cyclohexanedione) for use in the treatment of alkaptonuria, wherein nitisinone is administered in a dose of at least 4 mg per day. The invention also relates to a pharmaceutical composition comprising nitisinone for use in the treatment of alkaptonuria, wherein nitisinone is administered in a dose of at least 4 mg per day.