HOMEPRODUCTSCOMPANYCONTACTFAQResearchDictionaryPharmaSign Up FREE or Login

Time course of naloxone-precipitated withdrawal after acute methadone exposure in humans.

Abstract
This study examined naloxone-precipitated withdrawal symptoms from 24 to 168 h after pretreatment with a single 30-mg i.m. dose of methadone in 6 male subjects who were experienced users of opioid drugs but were not currently dependent. The study showed that acute physical dependence signs and symptoms could be reliably precipitated with a small dose of naloxone (0.75 mg/70 kg i.m.) for as long as 96 h (4 days) after a single dose of methadone. The intensity of symptoms at 24 h post-methadone was similar to that observed at 96 h; no precipitated withdrawal effects were observed at 168 h (7 days) after methadone administration. The magnitude of precipitated withdrawal effects at 96 h was not attenuated by the administration of a prior naloxone challenge at 24 h post-methadone. Agonist effects (pupillary constriction; subjective effects) were detectable at 24 h but not at 96 h post-methadone. The results suggest that methadone engenders long-lasting physical dependence effects that can be detected beyond the dissipation of acute agonist effects. Methadone pretreatments may provide a convenient mechanism for the production and examination of long-term mu-opiate receptor physical dependence.
AuthorsM L Stitzer, C Wright, G E Bigelow, H L June, L J Felch
JournalDrug and alcohol dependence (Drug Alcohol Depend) Vol. 29 Issue 1 Pg. 39-46 (Dec 1991) ISSN: 0376-8716 [Print] Ireland
PMID1665778 (Publication Type: Clinical Trial, Journal Article, Randomized Controlled Trial, Research Support, U.S. Gov't, P.H.S.)
Chemical References
  • Receptors, Opioid
  • Receptors, Opioid, mu
  • Naloxone
  • Methadone
Topics
  • Adult
  • Arousal (drug effects, physiology)
  • Humans
  • Injections, Intramuscular
  • Male
  • Metabolic Clearance Rate (physiology)
  • Methadone (administration & dosage, pharmacokinetics)
  • Naloxone (administration & dosage)
  • Neurologic Examination
  • Opioid-Related Disorders (physiopathology, rehabilitation)
  • Receptors, Opioid (drug effects, physiology)
  • Receptors, Opioid, mu
  • Substance Withdrawal Syndrome (physiopathology)

Join CureHunter, for free Research Interface BASIC access!

Take advantage of free CureHunter research engine access to explore the best drug and treatment options for any disease. Find out why thousands of doctors, pharma researchers and patient activists around the world use CureHunter every day.
Realize the full power of the drug-disease research graph!


Choose Username:
Email:
Password:
Verify Password:
Enter Code Shown: