OTTAWA - Health Canada is advising Canadians to read the labels of all prescription and over-the-counter medications to avoid accidental overdose of acetaminophen, which can lead to serious liver toxicity, and even death.

A recently published article identified acetaminophen overdose as the number one cause of acute liver failure in the US, and most of these overdoses were unintentional.1 Since acetaminophen is widely used and present in many preparations available in Canada, it is important to Health Canada that people read their medication labels carefully to ensure they are used safely.

Acetaminophen is a common ingredient used in both over-the-counter and prescription medications, and the public may be unaware of its presence in popular preparations for fever, pain, colds and flu. Often, several preparations of the same brand (e.g. Tylenol Pain and Tylenol Sinus) or several medications for the same symptoms (e.g. Tylenol Cold, Neo-Citran andSinutab) are found in the same household and, when used together, can result in an overdose.

For example, the parent of a child with a flu-like illness may use one product to treat the child's fever and another to treat a runny nose, without realizing that both products contain the same ingredients. In another instance, someone with chronic pain already on pain reliever combination products (such as Tylenol No.3 or Percocet) may decide to take an over-the-counter pill for fever without realizing that he or she is exceeding the recommended dose for acetaminophen.

Acetaminophen is safe when used as directed. Health Canada recommends that consumers not exceed the recommended dose on the drug label or use two products that contain the same ingredient (eg. acetaminophen) on the same day. Parents should be especially cautious when giving children any products containing acetaminophen.

When in doubt if a drug contains acetaminophen, consumers are advised to consult with their physician or pharmacist. In the event of a possible overdose, consumers should seek medical help immediately, even in the absence of symptoms, because early intervention is critical.

If current users of acetaminophen have concerns, they should speak with a doctor or pharmacist, because other pain relief choices may not be right for them.

Canadians should know that ALL medicines, both prescription and over-the-counter, have risks as well as benefits. Consumers are advised to read the labels of any drugs they are taking each and every time they are prescribed. For more information, please consult Health Canada's "It's Your Health" document about the safe use of medicines at http://www.hc-sc.gc.ca/english/iyh/.