What is a drug interaction?

A drug interaction is an altered drug response produced by another drug, chemical, or food that modifies the patient's response. The precipitant drug is the drug, chemical, or food causing the interaction; the object drug is the drug affected by it. Some interactions are intentional and beneficial - probenecid raises penicillin levels by decreasing renal excretion, and pentazocine + naloxone (Talwin NX) adds an antagonist to deter abuse. Interaction types include drug-drug, drug-herbal, drug-food/alcohol, drug-chemical, and drug-laboratory test interactions.

Two roles to keep straight: the PRECIPITANT causes the change; the OBJECT is the drug that gets changed. Interactions can be harmful or deliberately helpful.

📖 “Drug interaction = altered drug response from another drug/chemical/food. Precipitant drug causes it; object drug is affected. Types: drug-drug, drug-herbal, drug-food/alcohol, drug-chemical, drug-lab test.”