PHARMACOECONOMICS OF INTRAVENOUS ANTIBIOTIC USE IN SERIOUS INFECTION

A pharmacoeconomic study of 15 antibiotics available in Barbados was p erformed. The antibiotics studied were amoxycillin/clavulanate, ampici llin, ampicillin/sulbactam, cefazolin, cefotaxime, ceftazidime, ceftri xone, clindamycin, cloxacillin, cotrimoxazole, gentamicin, imipenem, m etronidazole, piperacillin, piperacillin/tazobactam, and vancomycin. T he costs of use of these compounds were calculated for a five-day cour se using a formula comprising eight categories: antibiotic purchase co st, maintenance of intravenous access, drug delivery cost, drug monito ring cost, dose readjustment, general monitoring cost, 'sharps' dispos al cost and adverse effects. The costs of adverse effects were not inc luded in this study due to lack of accurate data. The total cost of an tibiotic use (in U.S. dollars) ranged from $42.52 to $463.73 per five- day course. Generic compounds were less expensive ($45.52 - $98.23) th an brand-name compounds ($106.18 - $463.73). Antibiotic purchase costs accounted for proportions of total costs ranging from 7 to 93%. Non-d rug costs represented a much greater proportion of total costs of gene ric compounds. For most compounds the nondrug costs were related to th e frequency of dosing, but for gentamicin the non-drug costs were rela tively higher because of the need for monitoring of serum gentamicin l evels. Efficacy and freedom from side-effects will remain the most imp ortant determinants in the choice of antibiotic therapy. However, phar macoeconomic analyses can provide prescribers with the information req uired to make cost-effective choices for treatment of their patients.