A drug interaction happens when another substance affects the activity of a drug. Here are the types of interaction:

1. Drug-drug interactions happen when two drugs interact. For example, aspirin and warfarin are both blood thinners. Together, they increase the risk of bleeding and bruising.
2. Drug-food interactions occur when a food alters what the drug should be doing. For example, statins reduce cholesterol levels, but eating high-fat foods will increase them.
3. Drug-herb interactions can also happen, for example, using antidepressant medication with St. John’s Wort can provoke a hyperactive mood in a person with bipolar disorder.

Source: https://www.medicalnewstoday.com/articles/196135.php#from_medication