Levallorphan
An opioid antagonist with properties similar to those of NALOXONE; in addition it also possesses some agonist properties. It should be used cautiously; levallorphan reverses severe opioid-induced respiratory depression but may exacerbate respiratory depression such as that induced by alcohol or other non-opioid central depressants. (From Martindale, The Extra Pharmacopoeia, 30th ed, p683)