non-prescription medicine—sometimes called an over-the-counter, or OTC, medicine—is any drug that you can buy without a doctor's prescription. But don't assume that all non-prescription drugs are safe for you. These drugs can interact with other medicines and can sometimes cause serious health problems. And if you take more than the normal or recommended amount, overdose may occur.
Some medicines should only be used by adults or older children. Be sure to read the package instructions carefully, or ask a pharmacist before giving any product to an infant or young child. If you are pregnant, always check with your pharmacist or doctor before using any non-prescription medicine, to make sure it is safe to use during pregnancy.