Abstract: In the clinical trail phase II of compound prescription of cnidium fruit (containing volatile oil extracted form cnidium fruit), 11 cases out of 20 exhibited adverse reactions, such as dizziness, palpitation, sweating, choking sensation in chest, numbness in lips and tongue.After analyzing the relationship between the adverse reactions and the drug, the ethical review committees further examined the credibility of the ADR reports, the common features of the group from which adverse reactions arose, the influencing factors of adverse reactions, as well as the continuation of the trial with decreased dosage. Comparing with the expected benefits of functional impotence, other marked Chinese patent medicines, and the clinical acceptance, ADR unforeknowable and unpreventable, the risks of the trial drug were much greater. Consequently, ethical review committees made the decision of cessation of the trial.

Key words: cnidium fruit, adverse reaction, ethical review, clinical trials