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Narcotic analgesic
Includes morphine and morphine like drugs they act by
1. Depressing nociceptive neurons while stimulate non-nociceptive cells.
2. It elevates the threshold for painful stimuli
3. It alters the emotional reaction to pain
4. It produces sleep which also elevates the threshold
Morphine inhibits release of bradykinin when mediated by neural mechanism.
Addition of codeine to NSAIDS increases analgesic effect.
Narcotics are useful in managing severe acute pain and a=chronic cancer pain but contraindicated in chronic orofacial pain. These causes constipation, there fore stool softener and laxatives should be administered. They should be administered at regular time schedule
Clinician should be watch full for
1. Tolerance =larger dose are required to obtain satisfactory analgesic effect.
2. Physical dependence= withdrawal symptoms severe the condition
3. Addiction=compulsive caring for the drug and the need to use it for effects other than pain relief.
These enhance the analgesic effect of other medications [8].
Adjuvant analgesic or have independent analgesic activity in certain situations. These include tricyclic antidepressants antihistamine, caffeine, steroids, phenothiazines and anticonvulsants.