Effects of Garlic Supplements on Drug Metabolism
Drug: Garlic powder with high allicin content
Drug: Garlic powder with low allicin content
Drug: Garlic oil
Drug: Aged garlic
|Study Design:||Observational Model: Case-Only
Time Perspective: Prospective
|Official Title:||Garlic Metabolism and Cytochrome P450 Modulation|
- Blood plasma and urine samples [ Time Frame: 3 months ] [ Designated as safety issue: No ]
- Blood plasma and breath samples. [ Time Frame: 3 months ] [ Designated as safety issue: No ]
Biospecimen Retention: Samples With DNA
|Study Start Date:||July 2005|
|Study Completion Date:||March 2009|
Garlic supplements, which are often used to lower cholesterol and prevent cancer, are one of the most commonly used herbal products in the United States.
However, little is known about the way garlic supplements may interact with prescription medications when used simultaneously. This study will investigate four commonly used garlic supplements: garlic powder with a low content of allicin (a compound with antibacterial properties), garlic powder with a high allicin content, garlic oil, and aged garlic. The effects of these 4 garlic products on the drug-metabolizing enzyme cytochrome P450 (CYP) and a drug transporter, P-glycoprotein (Pgp) will be examined.
Participants will be randomly assigned to receive one of the four garlic supplements for 4 weeks. Drug probes of CYP and Pgp will be used to assess the in vivo activities of the substances. On the first day of garlic ingestion, blood collection will occur immediately after participants ingest their garlic supplement and 3, 4, and 6 hours after ingestion. Urine collection will occur immediately after participants' first garlic ingestion and 12, 15, and 72 hours after ingestion. Blood and urine collection will determine the concentration of the drug probes in the body, which will indicate changes in CYP and Pgp. Blood and urine tests will be repeated at the end of the study.
Please refer to this study by its ClinicalTrials.gov identifier: NCT00122889
|United States, Washington|
|Fred Hutchinson Cancer Research Center|
|Seattle, Washington, United States, 98109|
|Principal Investigator:||Danny D. Shen, PhD||Fred Hutchinson Cancer Research Center|