A drug interaction happens when a substance affects how a drug behaves in the body. Some substances that can cause interactions to include other drugs, supplements, food, and alcohol. Drug interactions do not only occur between prescription drugs. Over-the-counter drugs, food, supplements, and alcohol can all change the way the body metabolizes (breaks down) medication.

Read more to learn about different types of drug interactions, risk factors, and how to help prevent interactions by thoroughly reading drug labels.


Drug-drug interactions occur when one drug interacts with another. This is because a group of enzymes (called CYP450 enzymes) changes the way the body metabolizes warfarin. Drugs that inhibit these enzymes can increase the effects of warfarin, increasing the risk of dangerous bleeding. Drugs that induce the enzymes reduce warfarin’s effectiveness, raising the risk of blood clots.

These potentially dangerous health outcomes show how important it is to discuss new medications with a doctor or pharmacist. Inappropriately discarded drugs can harm people, animals, and the environment. It is essential to dispose of any unwanted medication safely.


While supplements are beneficial for people with a deficiency, they still have potential side effects and interactions, just like any other medication. The supplements a person takes can interact with prescription drugs or other supplements. When discussing medication with a doctor, a person should be sure to note any vitamins, supplements, and herbal remedies they take.

Alcohol and other recreational drugs

Alcohol and recreational drugs interact with many different drugs. They have the potential to interact with prescription drugs, supplements, and other recreational drugs.

Alcohol can interact with alcohol-containing drugs, such as cough syrup and laxatives. Consuming alcohol while taking these medications can intensify the effects of alcohol, which can be harmful.This means that the drug they are taking to treat their mental health condition may not be as effective if they also have a substance abuse disorder. If an individual or loved one is concerned about mental illness and substance abuse, they should contact a doctor