Impact of a practical two-stage intervention on aminoglycoside usage

Area of Science:

• Pharmacoeconomics
• Infectious Disease Management
• Health System Pharmacy Practice

Background:

• Aminoglycoside antibiotics are crucial for treating severe bacterial infections.
• Controlling the usage and associated costs of aminoglycosides is a significant challenge in healthcare settings.
• Therapeutic equivalence among different aminoglycosides necessitates strategic formulary management.

Purpose of the Study:

• To evaluate the impact of a two-stage intervention on aminoglycoside usage and costs.
• To assess the effectiveness of an automatic therapeutic interchange program for aminoglycosides.
• To determine the economic benefits and clinical appropriateness of the intervention.

Main Methods:

• Implementation of a two-stage intervention including an informational campaign and an automatic therapeutic interchange program.
• Removal of netilmicin from the formulary and substitution of gentamicin for tobramycin.
• Comparison of aminoglycoside order patterns during pre- and post-implementation periods (8 weeks vs. 24 weeks).

Main Results:

• New orders for netilmicin decreased from 42% to less than 1%.
• New orders for gentamicin increased from 50% to 90%, while tobramycin remained stable.
• An estimated annual cost saving of +27,000 was achieved with minimal pharmacy manpower and high prescriber acceptance.

Conclusions:

• A two-stage intervention effectively controlled aminoglycoside usage and reduced costs in a major teaching hospital.
• Automatic therapeutic interchange is a viable strategy for optimizing antibiotic formularies.
• The intervention demonstrated cost-effectiveness without compromising clinical appropriateness or prescriber satisfaction.