Drug Interactions Checker Start typing a drug name and select the best match from the list of suggestions. Repeat the process to add multiple drugs. Once your list is complete, you can check for interactions immediately or save your list for future reference. To view your previously saved lists, please sign in. What are drug interactions? Anytime you take more than one medication, or even mix it with certain foods, beverages, or over-the-counter medicines, you are at risk of a drug interaction.