drug interaction
Meaning of drug interaction: A drug interaction alters a medication's effect when combined with another substance, potentially strengthening, weakening, or otherwise changing its action.
Definition of drug interaction
A drug interaction is a change in how a medication behaves in the body that occurs because it is taken alongside another drug, an herbal product, certain foods, or in the presence of a particular medical condition. This change can make the original medication more potent, less effective, or can produce an effect that would not occur with the medication alone.
Drug interactions are broadly grouped by mechanism, including interactions that change how a drug is absorbed, broken down, or eliminated from the body, and interactions in which two substances act on the same target or body system in ways that add together or oppose one another. Some interactions develop gradually over repeated dosing, while others occur after a single combined exposure.
Because the number of possible drug combinations is enormous, identifying a clinically meaningful interaction generally relies on a combination of known pharmacology, reported case experience, and a careful review of everything a person is currently taking.
Used in a sentence
The pharmacist flagged a potential drug interaction between the newly prescribed antibiotic and the patient's existing medication.
Good to know
A drug interaction can involve foods, herbal supplements, or an existing medical condition rather than only other prescription medications, so a complete medication review generally considers all of these factors together.