[{"from": "human", "value": "Provide a brief overview of this molecule. [C][N][C][C][C][Branch1][Branch1][C][C][Ring1][=Branch1][O][C][Branch1][=Branch2][C][=C][C][=C][C][=C][Ring1][=Branch1][C][=C][C][=C][C][=C][Ring1][=Branch1]"}, {"from": "gpt", "value": "The molecule is an antihistamine. Antihistamines used in the treatment of allergy act by competing with histamine for H 1-receptor sites on effector cells. Antihistamines prevent, but do not reverse, responses mediated by histamine alone. Antihistamines antagonize, in varying degrees, most of the pharmacological effects of histamine, including urticaria and pruritus."}]