Hydroquinine (Inhibin®) has been approved for marketing in the Netherlands for the treatment of nocturnal cramps when treatment with drugs is considered necessary. It is available in the Netherlands since March 1990 as an over-the-counter drug with a dose of 200 mg with the evening meal and a further 100 mg at bedtime for 14 days. Hydroquinine also has antimalarial and demelanizing activity. It might be used to lightens light brown color patches on skin, age spots, skin discolorations associated with pregnancy, skin trauma or taking birth control pills. Hydroquinine is used in skin lightening creams and lotions because it is an effective bleaching agent, slowing the production of the tyrosinase enzyme and reducing the amount of melanin formed.