NCT06245564

Effect of Ketamine, Amitriptyline and Their Combination on Itch

Effect of Ketamine, Amitriptyline and Their Combination on Histaminergic and Non-histaminergic Itch

• Status: Completed
• Phase: N/A
• Study type: Interventional
• Enrollment: 30 (actual)
• Sponsor: Aalborg University · Academic / Other
• Sex: All
• Age: 18 Years – 60 Years
• Healthy volunteers: Accepted

Summary

Chronic itch affects approximately a fifth of the global population and is associated with substantial negative consequences for the affected individuals. Furthermore, there is a lack of efficient treat-ment options for chronic itch. Topical ketamine cream has been used successfully to relieve various forms of pain, and we hypothesize that topical ketamine relieves itch through a mechanism of action comparable to that in pain relief. The aim of this project is to evaluate the effects of ketamine both alone and in combination with amitriptyline on histaminergic and non-histaminergic itch induced by histamine and cowhage, respectively.

Detailed description

The main action of ketamine, 2-(2-chlorophenyl)-2-(methylamino)-cyclohexanone, is to antagonize the glutamate N-methyl-D-aspartate (NMDA) receptors. In the clinical setting, topical ketamine cream has been used successfully to relieve various pathogenic forms of pain. In addition to its pain-relieving effects, the cream was also reported to have itch-relieving properties in a very limited study. However, its efficacy on itch has not been established, and the mechanism of action remains uncertain. Ketamine cream is used not only by itself, but also in conjunction with other analgesics. One of these is amitriptyline, which may enhance the analgesic effects of ketamine. The aim of this human experimental study is to use the well-characterized anesthetic Ketamine, both alone and in combination with amitriptyline, as a tool to modulate different histaminergic and non-histaminergic itch modalities evoked by histamine and cowhage.

Conditions

• Itch

Interventions

Type	Name	Description
DRUG	Ketamine 0.5%	Ketamine cream 0.5% will be applied in a 4x4 area in the forearm of each participant.
DRUG	Amitriptyline	Amitriptyline cream 1% will be applied in a 4x4 area in the forearm of each participant.
DRUG	ketamine + amitriptyline	A cream containing ketamine 0.5%, amitriptyline 1%, will be applied in a 4x4 area in the forearm of each participant.
OTHER	Vehicle	A vehicle cream will be applied in a 4x4 area in the forearm of each participant.
OTHER	Histamine	After the cream removal, itch will be induced using histamine in the first session
OTHER	Cowhage	After the cream removal, itch will be induced using cowhage in the second session

Timeline

• Start date: 2024-08-20
• Primary completion: 2024-12-31
• Completion: 2024-12-31
• First posted: 2024-02-07
• Last updated: 2025-01-30

Locations

1 site across 1 country: Denmark