Top three things you should know about (the safe use of) acetaminophen

Acetaminophen, also known in other countries as paracetamol or APAP, is a safe and effective medication used to reduce fever and to treat pain, such as headaches, arthritis, and menstrual cramps.  It is found in many common over-the-counter (OTC) and prescription pain relievers and cold and flu medications.  Here are three things you should know about acetaminophen:

1 - It’s very easy to take too much acetaminophen. 

For most of us, when we think of acetaminophen, we probably think of a single ingredient product commonly known as the brand name Tylenol®. This is a product that we may have taken at some point in our lives to help reduce fever or treat a mild headache. Acetaminophen, however, is also found in a variety of OTC and prescription multiple ingredient products. Some examples of brand names that may contain acetaminophen include:  Percocet® or Oxycocet® (used for moderate or severe pain, including migraines and headaches), Benylin All-in-One® (used for cold and flu symptoms), and Midol® (used for relief of menstrual cramps).

Taking too much acetaminophen, on purpose or accidentally, may lead to liver toxicities. New products in Canada will display the words “contains acetaminophen” in bold, red text in the top right corner of the front of the package.  This will make it easier for consumers to know if a product contains acetaminophen and avoid overdosage. Manufacturers have until March 2018 to update labelling on all existing products.

2 - Dosing recommendations for acetaminophen differ across the border.

To reduce the risk of liver problems, Health Canada has recently improved the labelling standards for acetaminophen to provide a stronger and much clearer message regarding the risk of liver damage.  For adults, the lowest effective dose of acetaminophen should be used while not exceeding the recommended daily maximum of 4,000mg in a 24-hour period.  These products should also not be used for more than five days for pain or three days for fever without consulting a health professional.   

In the United States, the maximum doses and dosing interval were revised in 2011 to 3,000mg on some acetaminophen OTC products to protect consumers from inadvertent overdoses. Healthcare professionals may still prescribe or recommend a daily maximum of 4,000 mg to patients based on their own discretion and clinical judgment.

3 - Acetaminophen may not always be the best for that hangover.

As previously mentioned, taking too much acetaminophen may lead to liver toxicity.  In fact, it is the leading cause of acute liver failure in many countries, such as Canada and the United States. The chance for severe liver damage with its use is higher if you have liver disease and if you drink three or more alcoholic drinks per day.  

As acetaminophen is broken down or metabolized in the body in the liver, we require glutathione, an enzyme that naturally occurs in our bodies, to prevent liver injury. Chronic heavy drinkers tend to not eat well and have lower levels of glutathione, which then leads to liver damage.  

If you drink a lot of alcohol for one night and take a recommended dose of acetaminophen, you are probably not going to have liver problems - but be cautious if you have known liver issues or if you are a chronic heavy drinker.

Just remember, acetaminophen can be a safe and effective medicine to help reduce fever and treat pain when taken appropriately at the lowest effective dose for the shortest duration possible. 

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