indication

For the complete or partial reversal of narcotic depression, including respiratory depression, induced by opioids.

pharmacology

Levallorphan, an opioid antagonist similar to naloxone, is used to treat drug overdoses. Levallorphan differs from naloxone in that it also possesses some agonist properties. It is an analogue of levelorphanol that counteracts the actions of narcotic analgesics such as morphine. It is used especially in the treatment of respiratory depression due to narcotic overdoses. Levallorphan prevents or reverses the effects of opioids including respiratory depression, sedation and hypotension. Also, it can reverse the psychotomimetic and dysphoric effects of agonist-antagonists such as pentazocine.

mechanism of action

Levallorphan antagonizes opioid effects by competing for the same receptor sites. It binds to the opioid mu receptor and the nicotinic acetylcholine receptor alpha2/alpha3.

toxicity

Oral, rat LD₅₀: 109±4 mg/kg

biotransformation

Hepatic.

absorption

Rapidly absorbed.

half life

1 hour