A friend links to this article. The FDA has released a warning about products containing benzocaine (like Orajel).
The information in the article is worse than useless: it’s positively harmful because it’s going to make people worry about what appears at first glance to be a trivial risk. You have to click through to the FDA report to learn that 15 of the 21 were pediatric, and 11 of those 15 were under 2. It also isn’t clear from the kind of quick read most people are going to give this whether this is over a one-year period or over all time.
What are the possible consequences of methemoglobinemia, which I had never heard of until reading this? The NIH reports “shock, seizures, death” as possibilities, but with what probability? I’ve been hammering my students this semester on the differences between possible and probable: it’s possible that I will get a paper cut from one of the papers I’m grading and bleed to death, but it’s also so improbable as to not be worth my attention.
Further, a bit of perspective on these cases is in order. According to childstats.gov, there are 25.5 million kids between the ages of 0-5 in the US (best data I could get with a few seconds on The Google). For convenience, assume 10 million of them are under 2. Assume a quarter of those (2.5 million) have been treated with a benzocaine product for teething. If this estimate is anywhere close to accurate, then it means that 0.00044% of kids who were treated with benzocaine developed methemoglobinemia. Even if I’m off by a factor of ten, it’s still a fairly small risk. A first cut at a few numbers suggests that the relevant probability is close enough to zero to fall in the “not worth worrying about” category. I could be wrong and giving benzocaine to the kids could be the worst thing a parent could possibly do, but this information makes that far from clear.
There’s another important consideration: what are the incentives? Will the FDA go out of business if they are wrong? What incentive do they have to avoid the error of recommending against a product that’s actually pretty safe? This is a major problem because the FDA has every incentive to be dangerously cautious. They suffer a lot when they OK a dangerous drug. They hardly suffer at all when they fail to OK safe drugs even though both actions might exact the same costs.
I recommend Lenore Skenazy’s book “Free-Range Kids” for a very healthy perspective on risk. It’s definitely the best parenting book we’ve read (Bryan Caplan’s “Selfish Reasons to Have More Kids” is still on the shelf, waiting to be reviewed). A lot of what parents lose sleep over is so wildly improbable that our worry and the things we do in the name of those worries are more dangerous than the alleged threats themselves.