The present invention provides a pharmaceutical composition consisting of: a first pharmaceutically active part consisting of one or more cannabinoids; a second pharmaceutically active part consisting of one or more of glutathione, cysteine, acetylcysteine, alliin, briximine, carboxy methylcysteine, mucine, cat urine, lantidine, mesine hydrochloride, penicillamine cysteine disulfide, or any functional equivalent thereof; and a pharmaceutical composition comprising the first pharmaceutically active part and the second pharmaceutically active part, wherein the second pharmaceutically active part consists of one or more of glutathione, cysteine, acetylcysteine, alliin, briximine, carboxy methylcysteine, mucine, cat urine, lantidine, mesine hydrochloride, penicillamine cysteine disulfide or any functional equivalent thereof. And optionally one or more excipients; wherein the molar ratio of the second pharmaceutically active moiety to the first pharmaceutically active moiety is at least 0.5: 1, advantageously at least 1: 1. The composition of the present invention is advantageous in that it can prevent hepatotoxicity that may be caused by ingestion of isolated cannabinoids. The present invention also provides a method of manufacturing a pharmaceutical composition comprising the steps of: extracting a first fraction comprising one or more cannabinoids from cannabis plant material using a polar solvent; extracting a second fraction comprising glutathione from the same cannabis plant material using water; and drying and combining the first fraction and the second fraction to form the pharmaceutical composition.