Double-blind, randomized study of nalmefene and naloxone in emergency department patients with suspected narcotic overdose.
OBJECTIVE
To compare the efficacy, safety, and withdrawal symptoms in emergency department patients with suspected narcotic overdose treated with nalmefene, an opioid antagonist with a 4- to 10-hour duration of action, with those treated with naloxone.


METHODS
Adults in 9 centers who would otherwise receive naloxone for altered consciousness levels were randomly assigned to receive intravenous study drug (1 mg nalmefene, or 2 mg nalmefene or 2 mg naloxone, double-blinded) every 5 minutes as needed for up to 4 doses in a 4-hour study. Outcomes were 20-minute and 4-hour posttreatment changes in respiratory rates, Neurobehavioral Assessment Scale scores, Opioid Withdrawal Scale scores, and incidences of adverse events.


RESULTS
Opioid positivity was recorded for 30 of 63 (1-mg nalmefene), 23 of 55 (2-mg nalmefene), and 24 of 58 (naloxone) cases, 75% of whom also had nonopioid central nervous system depressants. Most patients received only 1 dose of study drug. Similar, clinically meaningful improvements in respiratory rates and Neurobehavioral Assessment Scale scores were seen with all treatments. No statistical differences in efficacy or withdrawal outcomes were seen between treatment groups, and no significant overall time-treatment interactions occurred, in either the entire patient group or among opioid-positive cases (P >.21, all comparisons). Adverse events occurred in 30.9% (2 mg nalmefene), 15.9% (1 mg nalmefene), and 15.5% (naloxone) of patients (P >.08); none were associated with morbidity.


CONCLUSIONS
In this study of patients with varied potential causes of altered consciousness, nalmefene (1 mg and 2 mg) and naloxone (2 mg) appeared to be efficacious, safe, and to yield similar clinical outcomes.
Kaplan
J L
JL
Department of Emergency Medicine, Albert Einstein Medical Center, 5501 Old York Road, Philadelphia, PA 19141, USA. kaplanj@aehn2.einstein.edu
Marx
J A
JA
Calabro
J J
JJ
Gin-Shaw
S L
SL
Spiller
J D
JD
Spivey
W L
WL
Gaddis
G M
GM
Zhao
N
N
Harchelroad
F P
FP
D000328:Adult; D004311:Double-Blind Method; D062787:Drug Overdose / Q000175:diagnosis / Q000188:drug therapy; D004638:Emergency Treatment / Q000379:methods*; D006801:Humans; D007275:Injections, Intravenous; D009270:Naloxone / Q000627:therapeutic use*; D009271:Naltrexone / Q000031:analogs & derivatives* / Q000494:pharmacology / Q000627:therapeutic use; D009292:Narcotic Antagonists / Q000494:pharmacology / Q000627:therapeutic use*; D009294:Narcotics / Q000506:poisoning*; D009460:Neurologic Examination; D012119:Respiration / Q000187:drug effects; D013997:Time Factors; D016896:Treatment Outcome
D009292:Narcotic Antagonists; D009294:Narcotics; D009270:Naloxone; D009271:Naltrexone; C038981:nalmefene