Acetaminophen Level

This test measures the amount of acetaminophen in your blood. Acetaminophen is a medicine used in many over-the-counter (OTC) and prescription medicines. It is used to relieve pain and reduce fever.

It comes in liquid, chewable, capsule, or pill form. It is found in many brand name medicines, including Tylenol and Excedrin. Outside the U.S., it's called paracetamol.

Acetaminophen can also be combined with other active ingredients in medicines that treat allergy, cough, colds, flu, and sleeplessness. Acetaminophen is safe when taken at the proper dose. However, taking too much of it can cause an acetaminophen overdose or toxicity.

This may cause serious and sometimes deadly liver damage. Unfortunately, it's common for people to accidentally take too much and have an acetaminophen overdose. It can happen if you: Take more than one medicine that contains acetaminophen.

For example, you may not realize that a cold, flu, allergy, or other medicine you are taking contains acetaminophen. If you take that medicine plus another medicine that contains acetaminophen, you may end up taking an unsafe dose.; Aren't following the dose recommendations in the instructions. For example, you might take more than the maximum dose or multiple doses more often than you are supposed to.

The adult maximum dose is generally 4000 mgs in 24 hours. But that may be too much for some people. Check with your health care provider to see how much medicine is safe for you.

Children's dosing recommendations depend on their weight, age, whether the medicine is in a liquid or solid form, if they are taking additional medicines that also have acetaminophen, and if they are taking any other medicines.; Give a child an adult version of the medicine, rather than the children's version.; Check with your provider before taking medicines containing acetaminophen for more than ten days, or five days for your child. When you take most medicines, including acetaminophen, your liver breaks them down and filters out the toxins. It may be hard for your liver to keep up if you're taking medicines containing acetaminophen for an extended time.

Why this test is done

Your provider may order this test if you or your child has symptoms of an overdose. When you take too much of the medicine, your liver cannot process the excessive dose and it can build up in your body. Symptoms may happen as soon as two to three hours after taking the medicine but can take as long as 12 hours to appear.

Symptoms in adults and children are similar and may include:

• Nausea and vomiting
• Diarrhea
• Abdominal (belly) pain
• Loss of appetite
• Trouble breathing
• Fatigue
• Irritability
• Sweating
• Jaundice, a condition that causes your skin and eyes to turn yellow

Acetaminophen overdose can be a life-threatening emergency if not treated quickly. If you think you or your child has taken too much acetaminophen, or you notice early symptoms of an acetaminophen overdose, call 911 or go to the nearest emergency room.

How to prepare

You don't need any special preparations for an acetaminophen level test.

Sample type

Blood

Other names for this test

acetaminophen drug test, acetaminophen blood test, Paracetamol test, Tylenol drug test, Paracetamol, Tylenol