PT - JOURNAL ARTICLE AU - Nat M J Wright AU - Michael J Campbell AU - Alison J Roberts AU - Victoria L Allgar AU - Charlotte N E Tompkins AU - Darren C Greenwood AU - Gillian Laurence TI - <span hwp:id="article-title-1" class="article-title">Impact of the CSM advice on thioridazine on general practitioner prescribing behaviour in Leeds: time series analysis</span><span hwp:id="article-title-10" class="sub-article-title">Commentary</span> DP - 2004 May 01 TA - British Journal of General Practice PG - 370--373 VI - 54 IP - 502 4099 - http://bjgp.org/content/54/502/370.short 4100 - http://bjgp.org/content/54/502/370.full SO - Br J Gen Pract2004 May 01; 54 AB - 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&lt;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.Commentary