This is interesting: from the Freakonomics blog:
Last time I was in London I had a headache, and went to the nearest Boots to buy something for it.
In U.S. drugstores, I’m accustomed to finding half an aisle devoted to headache pills, with bottles ranging from small to very large — at least 200 pills in them. So that’s what I went looking for in Boots, but no such bottle was to be found. The only options were cardboard packets containing maybe 20 pills, with each pill in its own blister packet. (The pills were also larger than U.S. pills.) Hmm, I thought. I guess Boots finds it can charge a lot for a small amount of headache medicine since most people, when they have a headache, aren’t very price-conscious.
[...] In England and Europe, Tylenol is sold under the name Paracetamol, and that’s used for huge numbers of overdoses, which on the whole aren’t lethal but leave the people with kidney damage and often of dialysis for the rest of their lives. They started doing that about five years ago, and they restrict the numbers, and they put them in plastic blisters so you have to tear them out. And again, you’d think all I have to do is go to six drugstores, you know, buy packets in each of them, all I have to do is just tear them out. But it has cut down the number of overdoses. It’s also cut down the number of serious overdoses that have led to kidney damage. Now, very few people died of an acetaminophen overdose. So it’s been hard to document that it cut the number of deaths, but certainly the number of attempts. The overdoses with it have been cut dramatically.
Hmm. Leaving aside the fact that APAP causes liver failure, not kidney failure, a factual error which makes this ER doctor cringe, this is actually kind of clever. They do something similar with kid's tylenol, which is deliberately sold in small bottles. Children's and Infant's Tylenol generally is sold in concentrations and quantities of 3g or so. The result is that if a curious 20-kg toddler decides to drink an entire bottle, they'll be getting a dose of 150 mg/kg, which is right at the threshold of serious toxicity -- and more importantly, is in an easily treatable range, even in a smaller child.
This makes sense to apply to the adult market. Tylenol is involved in at least 140,000 overdoses in the US annually (according to poison center databases (PDF); it may be much higher since many ER docs do not report tylenol overdoses, since many are non-toxic and we are very comfortable with treating them without poison center guidance). Of lethal overdoses, tylenol is in the top three, behind only opiates as a class, and cardiovascular drugs. So it's a non-trivial problem.
Would I, as a consumer, be annoyed at having to peel one of those damned blister packs to take a tylenol? Yes. It would be really irritating. But that's the point. The reason tylenol is so commonly implicated in overdoses is because it's convenient and readily accessible. Fairly few people who gulp half a bottle of tylenol are actually trying to die, few have any clue what the toxic OD is, and most are surprised when I tell them they took a potential lethal dose. It's perceived as a very safe drug. Some patients repetitively OD on tylenol precisely because they beleive from prior experience that it's safe. Putting tylenol in the blister packs woud not cut stop someone who is really determined and who does their homework, but those folks are hard to deter in any event. But it would certainyl cut down on the accidental/opportunistic overdoses.
It would be easy to do and it makes good sense. Which is why I'm quite sure that it'll never happen here in the US.