Switching off pain at the source: is this the end for opioid pain relief?

Opiates, like morphine or codeine, are used to suppress nociceptive pain in humans. While these drugs can provide effective pain relief, they also cause an extensive array of undesirable side effects, including central depression, sedation and addiction. Relatively recently, the sodium channel Nav1.7 was shown to be essential for pain perception in humans. Based on this, we describe a new technical approach that may be useful for the prolonged suppression of nociceptive pain. The technique uses a harmless adeno-associated virus carrying a short hairpin RNA to silence Nav1.7 ion channels only in sensory neurons underlying pain perception. The major advantage is that pain may be suppressed at the source for many months, without the side effects of opiates.