What Is Acetaminophen? - Definition, Uses & Side Effects

Instructor: Jennafer Tomlinson
Acetaminophen is a common over-the-counter medication, but what is it, and how does it work? After reading this lesson, you will know exactly what acetaminophen is, what it is used for, and what potential harmful effects it may cause.

What Is Acetaminophen?

Often, medications will have a generic name, also known as their drug name. They then are marketed at a lower cost than the brand names. Acetaminophen is the generic and drug name used for the medication commonly known as Tylenol. Acetaminophen is an over-the-counter medication, meaning it does not require a prescription from your doctor. This medication has numerous additional brand names, so it is important to clarify the medication you are taking with your pharmacist or physician.

Uses of Acetaminophen

Acetaminophen is commonly used to relieve pain and reduce fever, but only for a short period of time. As a pain reliever, acetaminophen can be used to relieve mild-to-moderate pain caused by a variety of ailments, including headaches, backaches, colds and sore throats, arthritis, menstrual cramps, and muscle aches.

How Does Acetaminophen Work?

When you are injured or experience pain, such as a sore throat, headache, or fever, nerve endings are believed to send signals to the brain, alerting it to the area of trouble. When the brain receives the message, it sends out pain signals. This helps us know if we have an issue that needs to be corrected. If we did not feel pain, how would we know if we were standing too close to fire or holding something sharp?

Researchers are unsure exactly how acetaminophen works. Some speculate that the medication blocks the signals nerve endings are sending to the brain, while others believe that the medication somehow works inside the brain itself. Let's look closer at how acetaminophen is thought to relieve pain and reduce fever.

  • Fever - Acetaminophen is an antipyretic drug, which means it is used to lower fever. When taken as directed, acetaminophen can work within the brain and central nervous system to block the chemicals given from the white blood cells, which can trigger a fever.
  • Pain - Acetaminophen is also an analgesic, which means it is a medication used to alleviate pain. When taken as directed, acetaminophen blocks the chemicals released by nerve endings sent to the brain. This action temporarily reduces the amount of pain you experience.

Side effects of Acetaminophen

Although acetaminophen is generally considered safe when taken as directed, it is possible for side effects to occur. It is essential that you contact a doctor immediately if any of the following side effects occur:

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