Polypharmacy
Our most complex patients are at highest risk for Drug-Drug Interactions. Polypharmacy, narrow therapeutic range of the medication, decreased hepatic and/or renal function of the patient each may increase the risk for DDIs. Each may be identified prior to coadministration. One should consider the potential for DDIs at all steps of the drug-delivery process. In a retrospective review of patients admitted to the emergency department, patients taking 3 or more medications or patients who were 50 years or older taking 2 or more medications had a considerable risk for DDIs. Furthermore, an increasing number of medications administered further increased the risk for adverse effects. Patients taking 2 medications had a 13% risk while patients taking 5 medications had a 38% risk for DDIs. Patients taking 7 or more medications had an 82% risk of developing adverse drug interactions. Advanced age is an additional risk factor for DDIs. Aparasu and colleagues found that the risk for DDIs increases...