Risks must be balanced

EDITOR —Until the Committee on the Safety of Medicines restricted the use of thioridazine in 2000, it was the most widely used antipsychotic drug in the United Kingdom, with 50 million years of safe use by patients worldwide. In Scotland in 1999, were 250 808 were prescriptions dispensed in primary care (hospital data not available, but the safety committee reports that it was the most widely used antipsychotic drug in hospitals too). This dropped to 39 177 in 2001, according to information from the Primary Care Information Unit in Edinburgh.

Is thioridazine safer, cheaper, and more effective than alternative antipsychotic drug treatments for anxiety, agitation, mania, and hypomania? We do not have enough evidence to answer this because thioridazine has been widely used for 30 years—before the days of rigorous randomised controlled trials. Lack of evidence is not evidence of no benefit. Conversely, there is only evidence of a handful of …