NCT00921765

Reversal of Ketamine Pharmacodynamic Effects With Naloxone

Naloxone Block of Low-dose (Analgetic Dose) Ketamine

• Status: Terminated
• Phase: Phase 4
• Study type: Interventional
• Enrollment: 3 (actual)
• Sponsor: Ullevaal University Hospital · Academic / Other
• Sex: Female
• Age: 18 Years – 30 Years
• Healthy volunteers: Not accepted

Summary

The purpose of this study is to determine whether the analgetic and other effects effect of ketamine are partly mediated through opioid receptors

Detailed description

Ketamine er et dissociative anaesthetic closely related with phencyclidine (PCP). Phencyclidine is a non-competitive NMDA-antagonist, and it is assumed that the pharmacodynamic mechanism of action for ketamine is the same. Receptor binding studies shows that ketamine has affinity to many receptor types, including opioid mu and kappa receptors. Ketamine has only about 25 times lower affinity for kappa receptors than for the NMDA-receptor complex. Naloxone is a specific antagonist for opioid receptors and block both mu og kappa receptors. A dose of naloxone 10 times larger than required to block mu receptors is required to block kappa receptors. Experiments with naloxone suggest that ketamine is not a mu agonist, but experiments with sufficient large naloxone doses to block kappa receptors have not been carried out in humans.

Conditions

• Pain

Interventions

Type	Name	Description
DRUG	Saline	Saline single bolus dose followed by saline single bolus dose iv
DRUG	Saline + Ketamine	Single bolus dose of saline followed by ketamine 0.2 mg/kg bw
DRUG	Naloxone + Placebo	Single bolus dose of naloxone 0.2 mg/kg bw followed by single bolus dose of saline
DRUG	Naloxone + Ketamine	Single bolus dose of naloxone 0.2 mg/kg bw followed by single bolus dose of ketamine 0.2 mg/kg bw

Timeline

• Start date: 2009-12-01
• Primary completion: 2017-12-01
• Completion: 2017-12-01
• First posted: 2009-06-16
• Last updated: 2018-04-05

Locations

1 site across 1 country: Norway