Cnidium: A plant genus of the family APIACEAE. Members contain osthol.Apiaceae: A large plant family in the order Apiales, also known as Umbelliferae. Most are aromatic herbs with alternate, feather-divided leaves that are sheathed at the base. The flowers often form a conspicuous flat-topped umbel. Each small individual flower is usually bisexual, with five sepals, five petals, and an enlarged disk at the base of the style. The fruits are ridged and are composed of two parts that split open at maturity.Diynes: Compounds with two triple bonds. Some of them are CYTOTOXINS.Antipruritics: Agents, usually topical, that relieve itching (pruritus).Coumarins: Synthetic or naturally occurring substances related to coumarin, the delta-lactone of coumarinic acid.Plant Extracts: Concentrated pharmaceutical preparations of plants obtained by removing active constituents with a suitable solvent, which is evaporated away, and adjusting the residue to a prescribed standard.