Oct 31 2007
Pain specialist Dr. Eske Aasvang of Denmark is trying a new compound in clinical pain relief trials: Capsaicin. Yes, the very same compound that makes hot peppers hot, and unwary college students who've never heard of chicken vindaloo before want to shoot themselves. Capsaicin, as it turns out, bonds tightly to the receptors of C-type nerve fibres, which trainsmit status messages to the brain that are interpreted as pain. Those receptors will fire briefly (as anyone who's ever eaten chili can attest to) but then go silent because the nerves will have exhausted their supplies of neurotransmitters. It is expected that this numbness will last for a couple of weeks, long enough for surgical incisions to heal. The idea is that surgeons will bathe the surgical sites with capsaicin solution before suturing so that the patient will require less analgesia after the general anesthetic is reversed. This isn't the only clinical trial of capsaicin as an anesthetic, though: At Harvard Medical School they are trying capsaicin in combination with epidural anesthetics in an attempt to develop saddle blocks that still allow the patient to walk, and the National Institutes of Health are working on using a capsaicin analogue as a non-opiate painkiller for cancer patients.