Thursday, March 4, 2010

Valuing Pain

Readers of this blog will know that I have some concerns about the regulation of pain medications. The FDA continues to warn about the issue of liver injury when taking acetaminophen.

For a moment, let's ignore the case of people taking the drug inappropriately or for whom another medication would provide better symptom control. They exist and are relevant to policy discussions, but they distract from today's main thought.

We can measure liver damage and death (hard outcomes). We cannot easily measure pain -- what level of pain relief is worth a 1% chance of death?

So do we leave it up to individual judgment? Drugs can be confusing and acetaminophen (due to efficacy) is included in a lot of preparations (for important reasons). So what is the ideal balance between these two goals (prevent adverse events and relieving pain)?

It would be so much easier if pain were easy to measure . . .


  1. And it's such an old drug... but surely somebody has published some sort of pharma-econ trial/s to quantify the pain effect?

    It might be worth pointing out to readers in the civilised world that this is actually paracetamol we're talking about.

  2. There are definitely pain trials and it is clear that acetaminophen {paracetamol} reduces pain. It's more trying to guess how much pain reduction is worth it at the cost of one life. Given how useful the drug is, I'm inclined to think that the trade-off is obvious but it's always going to be soft.

    I'm Canadian but we used acetaminophen as well but I got used to paracetamol when I worked with British data.

  3. NNK/T/H- Number needed to kill/treat/harm isn't going to work too well with subjective continuous data is it?

  4. Nope. Nor do I think suicides as compared to liver failures is really the right metric, either.

    I think quality adjusted years of life is likely to right general idea but it's hard to really decide on how much to discount "years filled with pain" over "years pain free".