ABSTRACT
This chapter reviews age-related changes in the body’s handling of medications and the body’s response to medications. It discusses definition, epidemiology, and consequences of polypharmacy; the related concepts of appropriate prescribing, errors of commission, and errors of omission; important drug–drug and drug–disease interactions in diabetes; and the epidemiology and predictors of drug adherence in diabetes. Although the intentions of prescribing multidrug regimens to manage diabetes and its complications are usually good, unintended negative consequences become progressively more common as the number of medications prescribed to frail elderly diabetic patients increases. Pharmacodynamic interactions between drugs can occur when they operate by different mechanisms to produce a shared effect on the same target organ. Factors associated with inadequate drug adherence in patients with diabetes include the patient’s comprehension of the treatment regimen and its benefits, adverse effects, medication costs, and regimen complexity, as well as their comorbid conditions.
