There are two categories of over-the-counter pain relievers/fever reducers: acetaminophen and nonsteroidal anti-inflammatory drugs (NSAIDs). Acetaminophen is used to relieve headaches, muscle aches and fever. It is also found in many other medicines, such as cough syrup and cold and sinus medicines. OTC NSAIDs are used to help relieve pain and reduce fever. NSAIDs include aspirin, naproxen, ketoprofen and ibuprofen, and are also found in many medicines taken for colds, sinus pressure and allergies.

These products, when used occasionally and taken as directed, are safe and effective. Read the labels of all your over-the-counter medicines so you are aware of the correct recommended dosage. If a measuring tool is provided with your medicine, use it as directed.

Using too much acetaminophen can cause serious liver damage, which may not be noticed for several days. NSAIDs, for some people with certain medical problems, can lead to the development of stomach bleeding and kidney disease.

There are many OTC medicines that contain the same active ingredient. If you take several medicines that happen to contain the same active ingredient, for example a pain reliever along with a cough-cold-fever medicine, you might be taking two times the normal dose and not know it. So read the label and avoid taking multiple medicines that contain the same active ingredient or talk to your pharmacist or health care professional.