This sounds absurd, but I hate the makers of Tylenol, McNeil and Co or whatever they're called. They have these commercials that say things like, "the one hospitals use most." Or they try to emphasize the safety of acetaminophen in one way or another as being easy one your stomach, and safe for kids.

What is not emphasized is what most doctors probably know (if they themselves don't believe the commercials), that Tylenol is probably the most dangerous over-the-counter medication sold.

The problem is people might be taking Tylenol for a few days for a headache (for which it's not that effective), or some other reason, and maybe they go out drinking and have maybe 2 or 3 glasses of wine. Then the next day, they're a little hungover, and they take more tylenol, and if they're real unfortunate, maybe they'll go out drinking again tonight. Then the next day, their liver has failed. It's called a "therapeutic misadventure" and it's really not difficult to do with the drug. It is also one of the most common drugs used for suicide. A study a few years back in Britain compared suicide numbers before and after Tylenol stopped being sold in bottles and instead was sold in smaller bubble packs (where you have to punch out each pill). Deaths from suicide dropped by about 30%, presumably because people couldn't just throw back a bottle of Tylenol pills anymore.

Now Jama reports that even the recommended maximum dose of 4g a day (which they have no business recommending) is dangerous. They stopped a study of some new acetaminophen/opiate mix because the patients liver enzymes were popping up under the so-called normal doses of tylenol.

None of the 39 participants assigned to placebo had a maximum ALT of more than 3 times the upper limit of normal. In contrast, the incidence of maximum ALT of more than 3 times the upper limits of normal was 31% to 44% in the 4 treatment groups receiving acetaminophen, including those participants treated with acetaminophen alone. Compared with placebo, treatment with acetaminophen was associated with a markedly higher median maximum ALT (ratio of medians, 2.78; 95% confidence interval, 1.47-4.09; P<.001). Trough acetaminophen concentrations did not exceed therapeutic limits in any participant and, after active treatment was discontinued, often decreased to undetectable levels before ALT elevations resolved.

3 times the upper limit of normal from the standard dose! Holy crap, how was this never seen before?

The lesson? The drug "Hospitals use most" isn't necessarily the safest drug to use. Hospitals use it because it not likely to cause stomach ulceration like NSAIDs (aspirin, ibuprofen, naproxen etc.) and it's a good fever reducer. That doesn't mean it's safe, or good for your problem (it's not that good a pain reliever compared to NSAIDs. Tylenol should only be used at normal doses for fever reduction in adults, pain reduction if they have problems with their stomach, and fever and pain relief in children (who should not take aspirin due to Rye syndrome risk). It also should never be used when one has been drinking, even a little bit.