There is limited clinical experience with REVIA (naltrexone) overdosage in humans. In one study, subjects who received 800 mg daily REVIA (naltrexone) for up to one week showed no evidence of toxicity.

In the mouse, rat and guinea pig, the oral LD50s were 1,100-1,550 mg/kg; 1,450 mg/kg; and 1,490 mg/kg; respectively. High doses of REVIA (naltrexone) (generally ≥1,000 mg/kg) produced salivation, depression/reduced activity, tremors, and convulsions. Mortalities in animals due to high-dose REVIA (naltrexone) administration usually were due to clonic-tonic convulsions and/or respiratory failure.

Treatment Of Overdosage:    In view of the lack of actual experience in the treatment of REVIA (naltrexone) overdose, patients should be treated symptomatically in a closely supervised environment. Physicians should contact a poison control center for the most up-to-date information.

REVIA (naltrexone) is contraindicated in:

1. Patients receiving opioid analgesics.
2. Patients currently dependent on opioids.
3. Patients in acute opioid withdrawal (see WARNINGS).
4. Any individual who has failed the naloxone challenge test or who has a positive urine screen for opioids.
5. Any individual with a history of sensitivity to REVIA (naltrexone) or any other components of this product. It is not known if there is any cross-sensitivity with naloxone or the phenanthrene containing opioids.
6. Any individual with acute hepatitis or liver failure.

Last reviewed on RxList: 12/8/2004
This monograph has been modified to include the generic and brand name in many instances.