Utilization of appetite suppressants in England: a putative indicator of poor prescribing practice.

The use of appetite suppressants, a putative inverse marker of prescribing quality, was analysed in the former Northern Regional Health Authority (RHA) and in England using National Health Service prescribing data and sales and patient-linked prescribing data supplied by Intercontinental Medical Statistics (IMS). The number (in thousands) of National Health Service prescriptions for appetite suppressants dispensed fell from 393 in 1991 to 235 in 1994. Per capita prescribing frequency varied threefold between different RHA and between individual Family Health Service Authorities (FHSA) within the former Northern RHA (NRHA). Prescribing frequency was higher in the spring and summer quarters and reduced in the winter quarter. Of 532 general practices in the NRHA, 82 (15%) prescribed no appetite suppressants between April 1993 and March 1994, while 70 (13%) prescribed more than 500 defined daily doses (DDDs) per 1000 patients, accounting for 47% of all prescribing. Only 53% of pharmacy purchases of appetite suppressants were accounted for by NHS prescribing and as little as 21% for phentermine, indicating substantial prescribing outwith the NHS. In 1991, 73,759 DDDs were supplied to pharmacies each day, the majority being diethylpropion (31,226) and phentermine (24,349). The fall in NHS prescribing is welcome as these drugs are of dubious clinical value and may be associated with serious adverse effects. Because of substantial non-NHS prescribing, routinely available prescribing data does not accurately quantify total prescribing of these agents.