Acute Liver Failure from Acetaminophen Overdose

Acetaminophen (Tylenol) overdose is the most common cause of acute liver failure in the United States.

Acetaminophen and Alcohol

Alcohol consumption substantially increases the risk of acute liver failure from acetaminophen overdose. According to the National Institutes of Health, liver damage may occur with consumption of only 2,600 mg of acetaminophen in the course of a day in people who have consumed varying amounts of alcohol. It is strongly recommended that people who consume alcohol on a regular basis limit acetaminophen intake to a maximum of 1,000 to 2,000 mg per day. The preference is to stay at the lower end of that range.

Regular-strength Tylenol tablets contain 325 mg of acetaminophen. Extra-strength Tylenol contains 500 mg, so this would mean consuming no more than two to four extra-strength pills within a 24 hour period. 

Other Over-the-Counter Medications with Acetaminophen

Acetaminophen is an active ingredient in more than 200 medications, including popular over-the-counter headache and cold remedies, including DayQuil, NyQuil, Anacin-3, Sudafed, Theraflu, Contac, Benadryl, Zicam and many others. For example, only one tablespoon of NyQuil or DayQuil contains 325 milligrams of acetaminophen. Since the standard recommended dose of both of these products is two tablespoons, most people will consume 650 mg in a single dose. That means that more than three doses in 24 hours would put you at serious risk of liver failure and death. NyQuil D has even more potential for liver danger since one tablespoon contains 500 milligrams of acetaminophen. Again, the recommended dose is two tablespoons, so most people will consume 1,000 mg with only one dose. Proctor and Gamble recently stopped manufacturing NyQuil D. See a list common over-the-counter and prescription medications containing acetaminophen

The Dangers of Liquid Medications

The liquid forms of these medications are particularly problematic. Many people simply take a gulp of medicine, rather than carefully measuring out a dose. Not measuring the dose significantly increases the risk of going beyond the limit for liver safety. All such liquid products should be carefully measured.

Always remember that a huge number of products contain acetaminophen. To protect the liver, it is crucial to never combine acetaminophen-containing products. Such combinations may very quickly put you at serious risk of liver failure. Carefully read the labels of all over-the-counter medications, as well as all prescription medications, in order to be certain that you never consume more than 1,000 to 2,000 mg of acetaminophen in any 24 hour period.

N-acetylcysteine (NAC) boosts the liver’s production of glutathione, the antioxidant used by the liver to safely detoxify acetaminophen and many other chemicals. By consuming NAC (500 mg, three times daily) on days you take acetaminophen, you can decrease the risk for serious liver toxicity. Never exceed the recommended daily limit of acetaminophen - even when taking NAC.