Systematic Approach to Managing Drug Interactions (2)

• Assess data in literature:

  • type of report, population studied, applicability to clinical practice

• Assess clinical significance:

  • depends on magnitude of interaction, therapeutic indices of drugs, potential consequences (e.g., impact on efficacy/toxicity)

Previous slide

Next slide

Back to first slide

View graphic version

• Once the potential for a significant interaction has been identified, the clinical significance must be determined.

• The clinical significance of an interaction will depend upon several factors, including:
  • the magnitude of change in pharmacokinetic parameters
  • the efficacy and toxicity of the affected agent(s).

• As already discussed, achieving and maintaining adequate antiretroviral concentrations may play an important part in successful and durable viral suppression. Since the risk of cross-resistance is high with protease inhibitors and NNRTIs, subtherapeutic drug levels should be avoided, in order to minimize the risk of resistance developing.

• In addition, the risk of drug toxicity may be higher with increased drug concentrations (e.g., ritonavir, indinavir)