title: Impact of the CSM advice on thioridazine on general practitioner prescribing behaviour in Leeds: time series analysis.
abstract: In December 2000, the Committee for Safety of Medicines (CSM) advised that thioridazine may prolong QT intervals risking arrhythmias. We investigated the impact on general practitioner prescribing of thioridazine using a time series analysis. Numbers of items and costs of antipsychotics and benzodiazepines prescribed in Leeds from May 1999 until April 2002 were collated. Post-advice, thioridazine prescriptions dropped by 810 items per month (95% confidence interval = 420 to 1200, P < 0.001) but others increased slightly in response. Costs mimicked these changes. Fresh criteria are proposed for appraising the quality of evidence needed to inform future urgent facsimile transmissions.
authors.affiliation: Centre for Research in Primary Care, Leeds. n.wright@leeds.ac.uk
authors.forename: Nat M J
authors.initials: NM
authors.lastname: Wright
authors.forename: Alison J
authors.initials: AJ
authors.lastname: Roberts
authors.forename: Victoria L
authors.initials: VL
authors.lastname: Allgar
authors.forename: Charlotte N E
authors.initials: CN
authors.lastname: Tompkins
authors.forename: Darren C
authors.initials: DC
authors.lastname: Greenwood
authors.forename: Gillian
authors.initials: G
authors.lastname: Laurence
mesh_terms: D014150:Antipsychotic Agents / Q000009:adverse effects*; D017277:Drug Approval; D004739:England; D005194:Family Practice / Q000379:methods*; D006801:Humans; D008133:Long QT Syndrome / Q000139:chemically induced*; D017410:Practice Guidelines as Topic; D010818:Practice Patterns, Physicians'; D012449:Safety; D012559:Schizophrenia / Q000188:drug therapy*; D013881:Thioridazine / Q000009:adverse effects* / Q000627:therapeutic use
chemical_list: D014150:Antipsychotic Agents; D013881:Thioridazine