Neuropathic pain: evidence matters.

"He slept less and less; they gave him opium and began to inject morphine. But this did not relieve him. The dull pain he experienced in the half asleep condition at first only relieved him as a change, but then it became as bad, or even more agonizing, than the open pain."--Tolstoy, The Death of Ivan Ilyitch. It comes as a surprise to many pharmacologists that not all pains are relieved by opioids. Those who work in chronic pain are unfortunately only too aware of the problems that such pains can cause. One of the hallmarks of neuropathic pain is poor or incomplete relief with opioids. As with so many things in medicine, there is nothing novel in this realization, as the Tolstoy quotation shows.