Drug Interactions: What You Need to Know

Drug interactions are among the most common and preventable causes of adverse medication events. They occur when one drug affects the behavior of another — altering its absorption, blood levels, effects, or metabolism — or when a drug interacts with a food, supplement, or medical condition to produce unexpected and potentially dangerous consequences. As the number of medications a person takes increases, the risk of interactions multiplies rapidly — and with nearly half of American adults taking multiple prescription medications, this is a genuinely widespread safety concern.

Types Of Drug Interactions

Pharmacokinetic Interactions: These affect how the body processes a drug — absorption, distribution, metabolism, or excretion (collectively, ADME).

Absorption interactions: Some drugs interfere with each other's absorption from the GI tract. Antacids, calcium supplements, and dairy products bind to certain antibiotics (tetracyclines, fluoroquinolones) in the stomach, significantly reducing their absorption. This is why these antibiotics must be taken either 1–2 hours before or 2–4 hours after such products.