Information about Naltrexone
Naltrexone is a synthetic opioid antagonist used in prevention of relapse of opiate adiction and alcoholism.
Liver safety of Naltrexone
Naltrexone has been associated with low rates of serum enzyme elevations during therapy and with rare instances of clinically apparent liver injury.
Mechanism of action of Naltrexone
Naltrexone (nal trex' one) is orally available opioid antagonist which blocks the euphoric effects of administered opiates. Naltrexone is a relatively pure antagonist and has no analgesic activity. Naltrexone has been shown to aid in maintenance of an opioid-free state in detoxified patients and to help in other addictions.
FDA approval information for Naltrexone
Naltrexone was approved for use in the therapy of opioid and alcohol dependence in the United States in 1984. Naltrexone is available in tablets of 50 mg in several generic formulations and under the brand name Revia. More recently, injectable suspensions of naltrexone (Vivitrol) and solutions of methylnaltrexone (Relistor) have become available.
Dosage and administration for Naltrexone
The usually recommended dose of the oral preparation is 50 mg daily. The injectable suspension is given intramuscularly and the solution subcutaneously every 4 weeks. Naltrexone must be started carefully in patients with opioid abuse to avoid precipitous withdrawal reactions.
Side effects of Naltrexone