Effect of Garlic Supplements on Opioids in Healthy Volunteers
Information source: National Cancer Institute (NCI)
Information obtained from ClinicalTrials.gov on August 08, 2008
Link to the current ClinicalTrials.gov record.
Condition(s) targeted: Healthy, no Evidence of Disease
Intervention: digoxin (Drug); garlic (Drug); midazolam hydrochloride (Drug); oxycodone hydrochloride (Drug); gene expression analysis (Procedure); laboratory biomarker analysis (Procedure); liquid chromatography (Procedure); mass spectrometry (Procedure); pharmacological study (Procedure); protein expression analysis (Procedure)
Phase: Phase 1
Sponsored by: Fred Hutchinson Cancer Research Center
Official(s) and/or principal investigator(s):
Danny Shen, PhD, Principal Investigator, Affiliation: Fred Hutchinson Cancer Research Center
RATIONALE: Garlic supplements may change the effectiveness of oxycodone used to relieve
moderate or severe pain.
PURPOSE: This randomized phase I trial is studying how garlic supplements may change the
effectiveness of opioids in healthy volunteers.
Official title: Modulation of Opioid Effects by Garlic Supplements
Study design: N/A
Primary outcome: Oxycodone hydrochloride pharmacodynamic measures
Secondary outcome: Oxycodone hydrochloride pharmacokinetic parameters
- Determine whether a CYP3A- and P-glycoprotein-dependent interaction exists between
garlic supplements and a commonly used oral opioid analgesic (oxycodone hydrochloride)
in healthy volunteers.
OUTLINE: This is a single-blind, randomized, crossover study. Participants are randomized to
1 of 2 arms.
- Arm I: Participants receive oral garlic twice daily on days 1-28 and oral oxycodone
hydrochloride on days 2 and 28. Participants then receive oral placebo twice daily on
days 58-87 and oral oxycodone hydrochloride on days 60 and 85.
- Arm II: Participants receive oral placebo twice daily on days 1-28 and oral oxycodone
hydrochloride on days 2 and 28. Participants then receive oral garlic twice daily on
days 58-87 and oral oxycodone hydrochloride on days 60-85.
In both arms, participants receive oral midazolam hydrochloride and oral digoxin once on days
29 and 86. Blood samples are collected periodically and examined by liquid
chromatography-mass spectrometry (LC-MS) for CYP3A4 and P-glycoprotein phenotyping.
Blood and urine samples are collected after receiving oxycodone hydrochloride for
pharmacokinetic-pharmacodynamic studies via LC-MS.
Pain response is assessed at baseline and periodically after oxycodone hydrochloride
treatment via electrical stimulation and the cold pressor test. Side effects of oxycodone
hydrochloride treatment are assessed via questionnaires and tests for cognitive function,
manipulative dexterity, motor speed, and visual attention.
Minimum age: 21 Years.
Maximum age: 45 Years.
- Healthy volunteer
- Body mass index 20-32
- Not pregnant
- No history of cardiopulmonary, liver, renal, endocrine, neurologic, or psychiatric
- No anemia
- No known adverse reactions to opioids, benzodiazepines, cardiac glycosides, or garlic
- No known allergy or hypersensitivity to sulfur-containing food or drugs
- No significant gastrointestinal intolerance to lactose in dairy products
- No recent history of alcohol or substance abuse
- No history of or concurrent heavy daily consumption of allium vegetables (i. e.,
garlic, shallots, leeks, and chives)
- No handicaps due to visual and hearing impairments
- No resting heart rate < 50 beats per minutes
- No abnormal cardiac rhythm by EKG
- No unusually sensitive response or resistance to pain stimulation (cutaneous
electrical stimulation and cold pressor test)
- Must be right handed
- No color blindness
- No history of learning disabilities or dyslexia
- Must be literate and proficient in English
- Must be a nonsmoker
PRIOR CONCURRENT THERAPY:
- No concurrent medication except oral contraceptives
- No concurrent grapefruit or grapefruit juice
- No other concurrent over-the-counter herbal products or herbal tea
Locations and Contacts
Fred Hutchinson Cancer Research Center, Seattle, Washington 98109-1024, United States; Recruiting
Danny Shen, PhD, Phone: 206-667-4583
Clinical trial summary from the National Cancer Institute's PDQ® database
Starting date: November 2006
Last updated: July 23, 2008