Pharmacology Of Dezocine

Indication Indicated in the treatment of moderate to severe pain.
Pharmacodynamics Dezocine is a parenteral narcotic analgesic possessing both agonist and antagonist activity. It is similar to morphine with respect to analgesic potency and onset and duration of action. The narcotic antagonist activity is greater than that of pentazocine.
Mechanism of action Dezocine is a opioid analgesic drug of mixed agonist-antagonist type. It binds with stereospecific receptors at many sites within the central nervous system (CNS) to alter processes affecting both the perception of pain and the emotional response to pain. At least 2 of these types of receptors (mu and kappa) mediate analgesia. Mu receptors are widely distributed throughout the CNS, especially in the limbic system (frontal cortex, temporal cortex, amygdala, and hippocampus), thalamus, striatum, hypothalamus, and midbrain as well as laminae I, II, IV, and V of the dorsal horn in the spinal cord. Kappa receptors are localized primarily in the spinal cord and in the cerebral cortex.
Absorption Rapid and complete following intramuscular administration.
Volume of distribution Not Available
Protein binding Not Available
Metabolism Hepatic, via conjugation (glucuronidation).
Route of elimination Not Available
Half life Elimination half-life following intramuscular administration averages 2.2 hours. Elimination half-life following a 5mg intravenous dose averages 1.7 to 2.6 hours (range 0.6 to 4.4 hours) while a 10mg dose averages 2.4 to 2.6 hours (range 1.2 to 7.4 hours). In patients with hepatic cirrhosis, the half-life is increased by 30 to 50%.
Clearance Not Available
Toxicity Symptoms of overdose include cold and clammy skin, confusion, nervousness, or severe restlessness, convulsions (seizures), severe dizziness, severe drowsiness, low blood pressure, pinpoint pupils of eyes, slow heartbeat, slow or troubled breathing and severe weakness.