This usually occurs when the individual is aroused and mentally preoccupied with something other than the pain, for example, participating in sports of combat. It is only later, when the emotional intensity subsides, that the severe pain is experiences. We now know that the brain has circuits specifically designed to control the pain pathways, and there is good evidence that the most powerful painkillers, the narcotics such as morphine and codeine, act rather selectively upon pain-controlling circuits while preserving consciousness and other sensory systems such as vision and hearing. Furthermore, one of the most remarkable discoveries of the past 20 years was that some brain cells manufacture compounds that act like narcotic painkillers. The challenge now is to use these advances in our understanding of endogenous pain control mechanisms to benefit patients.
Surgical intervention can block the pain message at the spinal cord.
The treatment of pain Most acute pains can be managed satisfactorily with currently available methods. Postoperative pain can also be well-controlled. In contrast, we are a long way from our goal of controlling chronic pain. In the hospital, side effects such as drowsiness, depressed breathing and nausea are acceptable because the patient is protected and monitored, and the phenomenon called tolerance by which a painkiller eventually becomes ineffective is not a problem, because the need is short-term. But in treating chronic pain, sedation and tolerance are both unacceptable and unfortunately virtually all of the most potent painkillers share these drawbacks.