Profiles of antibacterial drug use in Australia and trends from 1987 to 1989: A report from the Drug Utilization Subcommittee of the Pharmaceutical Benefits Advisory Committee

Abstract

To survey the use by Australian pensioners of orally administered antimicrobial agents supplied through the Pharmaceutical Benefits Scheme over the years 1987-1989. Australian Pharmaceutical Benefits Scheme pensioner data for 1987-1989 and market research data from a private company. The data were initially available as the number of prescriptions dispensed and were aggregated on a quarter year basis. These were converted to defined daily doses (DDDs) per 1000 pensioners per day (DDD/1000 per day). This conversion of the data allows comparisons across drug groups, and with prescribing patterns in other countries. The DDD/1000 per day also gives an indication of the proportion of individuals in the community receiving a drug at a particular time. There was a 26% increase in antibacterial drug use over this period. Comparison of prescribing profiles for particular indications with peer consensus guidelines revealed marked discrepancies, particularly for upper respiratory tract infections, urinary tract infections, otitis media and sinusitis. Upper respiratory tract infections accounted for 31% of instances of antibiotic prescribing. Dispensing of amoxycillin/potassium clavulanate relative to amoxycillin as a single agent, showed a marked increase in 1989 to the point where it represented 25% of all amoxycillin used. This could be considered excessive given the lack of evidence that amoxycillin resistance has substantially increased in infections presenting to general practice. The data presented here confirm previous suggestions that Australian antibiotic prescribing is heavily concentrated on the use of broad spectrum agents. By comparison with Norway or Sweden, there is a greater relative use of broad spectrum penicillins and tetracyclines and a lower relative use of phenoxymethylpenicillin and trimethoprim. Antibiotic prescribing practices in Australia continue to be often inappropriate and expensive, being directed too heavily towards the use of broad spectrum agents and newer more expensive drugs. Correction of such antibacterial drug use will require coordination of educational and regulatory activities that are sensitive to the context of general practice.