Naltrexone overdose

Accidental naltrexone overdose produces withdrawal symptoms within 5 minutes of ingestion that may last for up to 48 hours. Symptoms include confusion, visual hallucinations, somnolence, and significant vomiting and diarrhea. 

Opioidergic agents. Naltrexone and nalmefene, opioid antagonists with no intrinsic agonist properties, have been studied for the treatment of alcohol dependence. Naltrexone has been studied much more extensively than nalmefene for this indication. In 1984 naltrexone was approved by the FDA for the treatment of opioid dependence, and in 1994 it was approved for the treatment of alcohol dependence. Nalmefene is approved in the United States as a parenteral formulation for the acute reversal of opioid effects (e.g., after opioid overdose or analgesia). 

Naltrexone (Trexan) is the only opioid antagonist currently in use for treatment of addiction. Naloxone is used to treat opioid overdose and to test for opioid addiction but has a short half-life and is relatively ineffective orally cyclazocine s dysphoric side effects make it unacceptable (Resnick et al. 1980). Patients who are likely to continue to use naltrexone and to benefit from treatment are those who have established careers (e.g., health professionals) and family support and are well motivated. Up to 70% of such clients are abstinent at 1-year follow-up (Washton et al. 1984). Programs that utili2e additional rehabilitative services have better results than those that provide minimal services. Successful treatment is also associated with taking naltrexone... 

The opioid antagonists naloxone and naltrexone bind to aU three opioid receptors, p, K, and 8. These compounds are antagonists due to their inability to elicit downstream effects of these receptors once bound (Sarton et al. 2008 Yaksh and Rudy 1977). Interestingly, both antagonists have a high binding affinity for MORs. Naloxone is used to reverse the effects of an acute opioid overdose because of its rapid onset of action. Naltrexone elicits similar actions, but has a longer onset and duration of action and hence, is used for the maintenance of treatment for opioid addicts. 

Naloxone (Narcan). Naloxone, like naltrexone, is a potent opioid receptor blocker. Its primary use has been to reverse opiate toxicity after an overdose. However, some physicians have found it is also useful for a process known as rapid opiate detoxification. Although opiate withdrawal is not life threatening, it can be extremely unpleasant. Most opiate addicts are fearful of the withdrawal symptoms therefore, it usually requires a slow, deliberate detoxification to keep the withdrawal symptoms in check. Rapid opiate detoxification is an alternative approach that keeps the taper and detoxification as brief as possible. In this approach, naloxone is used in conjunction with general anesthesia or a nonopiate sedative such as the benzodiazepine mid-... 

There are no reports about toxic reactions following ingestion of an overdose of naltrexone. 

When given intravenously to a morphine-treated subject, the antagonist completely and dramatically reverses the opioid effects within 1-3 minutes. In individuals who are acutely depressed by an overdose of an opioid, the antagonist effectively normalizes respiration, level of consciousness, pupil size, bowel activity, and awareness of pain. In dependent subjects who appear normal while taking opioids, naloxone or naltrexone almost instantaneously precipitates an abstinence syndrome. 

In studies of its use in treating alcohol, opioid, and nicotine dependence, naltrexone has not been reported to cause depression or dysphoria. Patients who complain of naltrexone-associated dysphoria often have co-morbid depressive disorders or depression resulting from opioid or alcohol withdrawal states (549). Co-morbid depression is not a contraindication to naltrexone. Small pilot studies have supported the use of naltrexone in combination with antidepressants for the treatment of patients with co-mor-bid depression. The risk of non-fatal overdose is significantly increased after naltrexone treatment, as a result of reduced tolerance, compared with patients taking substitution methadone (550). 

Ritter AJ. Naltrexone in the treatment of heroin dependence relationship with depression and risk of overdose. Aust NZ J Psychiatry 2002 36(2) 224-8. 

Opioid antagonists (Table 7.4), predominantly naloxone, are used clinically to reverse the effects of opiates in overdose or postoperative sedation. Naltrexone, which has oral bioavailability, is used for the treatment of narcotic addiction and alcohol dependence. As discussed below (Section 2.2.2.1), peripherally selective antagonists are being evaluated for treatment of constipation and other gastrointestinal side effects associated with opioid agonist use. 

The 17 - N- a 11 y I - (n a I o x o n e. 3a) and 17 - /V-c v c lop I opv I m e t h v I (naltrexone, 3b) analogues of oxymorphone (2d) are the prototype opioid receptor antagonists with some selectivity for MOR. They have entered clinical practice as treatments for narcotic overdose (naloxone) and alcoholism or opioid abuse/dependence (naltrexone). The 17-quatemary derivative of naltrexone, methylnaltrexone (4) has recently been introduced into clinical practice as a treatment for opiate-induced bowel dysfunction [1],... 

Nalmefene, a derivative of naltrexone, is used in therapy of opiate overdose. 

Attention to nutritional needs is not totally protective against organ system damage that occurs with chronic abuse of alcohol. Females are more susceptible to alcohol hepatotoxicity than males. Respiratory depression is a symptom of ethanol overdose, not withdrawal. Naltrexone, an opioid receptor antagonist, may have value in some patients to decrease the intensity of craving. The answer is (C). 

Pain-relieving action is not superior to that of codeine Response to naloxone in overdose may be unreliable This drug, which does not activate opioid receptors, has been proposed as a maintenance drug in treatment programs for opioid addicts a single oral dose will block the effects of injected heroin for up to 48 hours (A) Amphetamine Buprenorphine Naloxone Naltrexone Propoxyphene... 

Cocaine intoxication has become a common problem in hospital emergency rooms. Which one of the following drugs is not likely to be of any value in the management of cocaine overdose (A) Dantrolene Diazepam Lidocaine Naltrexone Nitroprusside... 

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