One of the more sobering parts of being a trial lawyer is reviewing intakes of potential cases. We routinely talk with people who have just lost a spouse or child or who have recently suffered an injury that will leave them permanently disabled. Many of these accidents happened in the course of activities we all know to have an element of danger, but many involve doing the same thing a million other people do every day. No one expects that giving their kid Motrin will cause a horrific skin disease or that their tap water might be so polluted that it’s flammable.
Now, a growing body of medical studies shows that acetaminophen (Tylenol in the US, Paracetamol everywhere else) is dangerous at far lower doses than previously believed. It’s been known for decades that acetaminophen overdoses cause liver damage (for example, “acetaminophen hepatotoxicity far exceeds other causes of acute liver failure in the United States,” and some estimates by the American Association of Poison Control Centers suggest more than 50,000 emergency department visits every year related to acetaminophen), particularly when combined with alcohol, but it was generally considered safe if taken at anywhere near the recommended amounts.
Recent studies suggest that’s not the whole story. Just a few weeks ago, a new study in the British Journal of Clinical Pharmacology found that “staggered overdoses,” in which patients repeatedly took amounts slightly higher than the recommended dosage, were the cause of a substantial portion of the hospital admissions for acetaminophen-induced liver damage, and could be more dangerous than individual overdoses, in part because staggered overdoses were harder to diagnose and treat.
In June 2009, the FDA’s Drug Safety and Risk Management Advisory Committee, Nonprescription Drugs Advisory Committee, and the Anesthetic and Life Support Drugs Advisory Committee all voted in favor of:
- Reducing the current dosage strengths of acetaminophen in nonprescription products to below 4 grams/day
- Limit formulations of over-the-counter liquid doses of acetaminophen
- Eliminating prescription acetaminophen combination products (e.g., oxycodone)
- Requiring a boxed warning for prescription acetaminophen combination product
The FDA disappointingly didn’t act on most of that, and instead took eighteen months to take the weakest action it could:
On January 13, 2011, FDA announced that it is asking manufacturers of prescription acetaminophen combination products to limit the maximum amount of acetaminophen in these products to 325 mg per tablet, capsule, or other dosage unit. FDA believes that limiting the amount of acetaminophen per tablet, capsule, or other dosage unit in prescription products will reduce the risk of severe liver injury from acetaminophen overdosing, an adverse event that can lead to liver failure, liver transplant, and death.
The size of the individual dosage unit was never the problem, though. As the Acetaminophen Hepatotoxicity Working Group for the FDA Advisory Panel found in its report, the problem was far more complicated than the pills being too big:
There is no single factor that leads consumers (also referred to as patients in this report) to develop acetaminophen-related liver injury. The contributing conditions for these cases are multi-factorial and require different interventions that attempt to address each factor. For example, when someone takes an amount greater than labeled, it is unclear whether it is a case of failing to read the directions, failing to understand the directions, failing to understand that severe liver injury can result from not following the directions or failing to realize that more than one of the medications used contained acetaminophen.
The Working Group concluded, “Thus, it is necessary to address all of these causes in attempting to prevent future cases, making clear directions conspicuous and easy to understand and making consequences of overdose unequivocally clear.” (Emphasis added.)
It’s not just the pill size. It’s not just the recommended maximum dosage. The core problem is that consumers and patients have learned, from years of Tylenol advertising and liberal use of acetaminophen by their parents, nurses, and doctors, that it’s a “safe” drug, like caffeine, that can be used every day and without much consequence unless you have a particular susceptibility to it or if you intentionally take way too much. Consumers look at recommended dosages like they do speed limits: you can use that amount without any problems, but try not to go too far above it. Problem is, if you did that with the 4 grams/day of acetaminophen guideline, you had a much higher risk of liver damage, even if you didn’t do it all the time.