pharmacokinetic interaction
Pronunciation: far-muh-koh-ki-NET-ik
Drug interaction that affects the absorption, distribution, metabolism, or elimination of medications, altering their blood concentrations.
Full Definition
Pharmacokinetic interactions occur when one drug affects the absorption, distribution, metabolism, or elimination (ADME) of another drug, resulting in altered plasma concentrations and potentially changed therapeutic effects. These interactions commonly involve the cytochrome P450 enzyme system, where one drug may inhibit or induce enzymes responsible for metabolizing another medication. In neuropsychiatry, such interactions are particularly important given the narrow therapeutic windows of many psychotropic medications and the potential for serious adverse effects. Examples include certain antidepressants affecting antipsychotic metabolism or anticonvulsants inducing the metabolism of other psychiatric medications.
Usage
Usage note: Distinguish from pharmacodynamic interactions (affecting drug action at target sites). Critical in polypharmacy management.
In Context
- "The psychiatrist adjusted the antipsychotic dose due to a pharmacokinetic interaction with the newly prescribed anticonvulsant." — Medication management note
- "Pharmacokinetic interactions were carefully monitored when combining the SSRI with medications metabolized by CYP2D6." — Clinical pharmacology consultation