Plasma Concentration of Ketamine and Norketamine .

NCT02016664 | Completed

• 1 other identifier: OKPCS
• Study Type: interventional
• Target: 12
• Locations: 1 country
• Sites: 1

Brief Summary

Oral ketamine is increasingly used by doctors to both reduce the amount of narcotic pain medication consumed and to improve chronic pain management in difficult cases. How much is absorbed when taken orally, as opposed to intravenously ,is unknown. Ketamine may cause sedation, and occasionally cognitive impairment. Therefore, there are safety concerns associated with its usage as an out-patient may engage in activities where cognitive impairment is dangerous,such as driving. This study is designed to measure the plasma concentrations of ketamine and its active metabolite, norketamine, in people taking low dose oral ketamine for chronic pain. The goal of the study is to verify that low dose oral ketamine produces plasma concentrations below the level associated with toxic symptoms,and thus can be safely used long-term for the treatment of chronic pain .

Conditions

Chronic Pain

Keywords

Chronic Pain, Ketamine, Safety

Outcome Measures

Primary Outcomes (1)

• Plasma level of oral ketamine and norketamine at two different doses.

  Plasma level of ketamine and norketamine will be tested just before ingestion of oral ketamine (trough level) and then after at 30,60,90 and 120min. Patients will be already using oral ketamine therapy for 7 days before the test. This test will be repeated twice on 2 different doses (10 and 2o mg q 8 hr).

  0,30,60,90 and 120 min after ingestion.

Secondary Outcomes (1)

• Mean Pain Score

  week 1 and week 2

Study Arms (1)

Chronic pain patients on oral ketamine

EXPERIMENTAL

Days 1-7: Subjects will be given a 7 day supply of 10 mg ketamine tablets three times per day for seven days and to return to clinic on Day 7. They will be instructed not to take their morning dose of ketamine and to eat a light breakfast on Day 7. Upon arrival, the patient will have a 20 gauge (saline locked) IV started in the antecubital fossa to allow for five blood samples: Time Zero,30, 60,90 and 120 minutes. The first blood sample at Time 0 will be obtained just before the patient takes his/her oral dose of ketamine. Days 8-14: The subjects will be given a supply of 20 mg ketamine capsules and instructed to take them three times per day, at specified times, and to return to clinic on Day 14. The instructions and procedures at the second clinic visit will be the same as on Day 7.

Drug: Ketamine

Interventions

Ketamine DRUG

The St.Joseph's Heath Care Pharmacy will supply the compounded oral ketamine capsules. Patients who are going to participate in this study are already taking this oral ketamine as a part of their chronic pain medications. No new patient will start oral ketamine for the sake of this study. Two doses of oral ketamine will be used for the same patient, 10 mg and 20 mg every 8 hours. These doses are the standard doses in our clinic. Other clinics using much higher doses.

Chronic pain patients on oral ketamine

Eligibility Criteria

• Age: 18 Years - 75 Years
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Patient currently takes oral ketamine for the treatment of chronic neuropathic pain.
• Age \>18 and \< 75 years
• Both males and females 4.Ability to speak English adequately to understand the consent and participate in the study
• No other route of ketamine within past 7 days (Topical/IV)

You may not qualify if:

• Patient receiving liver enzyme inducers or inhibitors of Cytochrome CYP3A4, or CYP2B6 like clarithromycin, rifampin, and recent ingestion of grapefruit juice.
• Patients who have had gastric bypass surgery
• Patients who did not follow the prescribed protocol
• Renal Failure defined as Creatinine Clearance \<50 mL/min
• Hepatic insufficiency by history

Sponsors & Collaborators

• London Health Sciences Centre Research Institute OR Lawson Research Institute of St. Joseph's: lead

Study Sites (1)

St.Joseph's Health Care, Western University

London, Ontario, N6A4V2, Canada

Location

MeSH Terms

Conditions

Chronic Pain

Interventions

Ketamine

Condition Hierarchy (Ancestors)

Pain; Neurologic Manifestations; Signs and Symptoms; Pathological Conditions, Signs and Symptoms

Intervention Hierarchy (Ancestors)

Cyclohexanes; Cycloparaffins; Hydrocarbons, Alicyclic; Hydrocarbons, Cyclic; Hydrocarbons; Organic Chemicals

Study Officials

• Patricia Morley-Foster, MD, FRCPC

  Department of Anesthesia and Perioperative Medicine, Western University, Canada.

  PRINCIPAL INVESTIGATOR

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: NA
• Masking: NONE
• Intervention Model: SINGLE GROUP
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Clinical Fellow

Study Record Dates

• First Submitted: December 16, 2013
• First Posted: December 20, 2013
• Study Start: April 1, 2014
• Primary Completion: December 1, 2015
• Study Completion: December 1, 2015
• Last Updated: March 1, 2016

Record last verified: 2016-02

Locations

CA (1)