At peripheral pain sites, nonopioid analgesics, heat and cold application, and local anesthetics can alter the release of nociceptive substances and reduce muscle spasms. In the spinal cord, epidural analgesics, tricyclic antidepressants, neurosurgical procedures, and stimulation of large nerve fibers by direct electrical stimulation, massage, heat and cold application, and therapeutic touch can interfere with nerve impulse transmissions. In the brain stem, electrical stimulation, tricyclic antidepressants, opioid analgesics, and neurosurgical procedures can reduce or eliminate the transmission of pain impulses. In the cerebral cortex, cognitive techniques such as hypnosis, imagery, music therapy, relaxation, behavioral training, and opioid analgesics provide additional ways to control pain. 7 Pharmacological management of chronic pain includes non-narcotic analgesics, narcotic analgesics, and psychotropic drugs.
Narcotic analgesics range from weak to strong opioid drugs.
Effective oral doses of oral narcotics range from 15 to 30 mg a day of morphine or its equivalent. Systemically absorbed opiates can produce many undesirable gastrointestinal side effects such as constipation, nausea, and vomiting and also produce sedation that results in memory impairment, drowsiness, and impaired concentration. Other common side effects of opioid analgesics are fatigue, weakness, and central nervous system depression. 4 Older patients may have increased sensitivity to the analgesic effects of medications and may have more central nervous system side effects, such as confusion, dizziness, and drowsiness. Aging affects the absorption, detoxification, and excretion of medications, increasing toxicity risks and adverse reactions.