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An Assessment of Milk Thistle Pharmacokinetics and Drug Interactions

The recruitment status of this study is unknown. The completion date has passed and the status has not been verified in more than two years.
Verified December 2009 by Medical University of South Carolina.
Recruitment status was:  Recruiting
National Center for Complementary and Integrative Health (NCCIH)
Office of Dietary Supplements (ODS)
Information provided by:
Medical University of South Carolina Identifier:
First received: September 13, 2005
Last updated: December 9, 2009
Last verified: December 2009
There is accumulating evidence from various sources that extracts from the milk thistle plant can be useful in the treatment of a variety of liver ailments as well as other disorders. This investigation will essentially be composed of two individual normal volunteer studies of milk thistle. The first study will assess the rate and extent of absorption of components of a standardized botanical extract obtained from the milk thistle plant. This first study is termed a bioavailability study. This investigation will take approximately 8 weeks and involve 10 clinic visits. Secondly, a drug interaction study will be performed. This is an assessment study of the potential for this botanical extract to interact with other prescription or over-the-counter medications. This study is also expected to take approximately 8 weeks but will involve 18 clinic visits. In both studies all subjects will receive the same milk thistle supplement and no placebo will be administered.

Condition Phase
Phase 2

Study Type: Observational
Study Design: Time Perspective: Prospective
Official Title: Pharmacokinetics and Drug Interactions With Milk Thistle

Resource links provided by NLM:

Further study details as provided by Medical University of South Carolina:

Biospecimen Retention:   Samples Without DNA
plasma & urine

Estimated Enrollment: 32
Study Start Date: May 2006
Estimated Study Completion Date: August 2007
  Show Detailed Description


Ages Eligible for Study:   18 Years to 45 Years   (Adult)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   Yes
Sampling Method:   Non-Probability Sample
Study Population
Normal healthy volunteers

Inclusion Criteria:

  • Age range: 18-45 years old
  • Race or ethnicity: no restrictions
  • Health status: subjects must have no clinically significant diseases or clinically significant abnormal laboratory values as assessed during the screening medical history, physical exam, and laboratory evaluations.
  • Must have no history of significant psychiatric illness or substance use.
  • Written Informed Consent as well as Health Insurance Portability and Accountability Act (HIPAA) authorization forms must be signed by the eligible subject prior to the initiation of any study procedures.

Exclusion Criteria:

Any of the following conditions are cause for exclusion and/or discontinuation from the study:

  • The presence of any surgical or medical condition (active or chronic) that may interfere with drug absorption, distribution, metabolism, or excretion.
  • A positive urine pregnancy test
  • The use of oral contraceptives
  • The lack of use of acceptable barrier methods of birth control unless abstinent
  • The use of any concomitant medication including herbal medications, over-the-counter (OTC) supplements, or a history of hypersensitivity to DM, ALPZ, TOL, or caffeine (CAF) and any history of sensitivity to milk thistle or any of its components.
  • Subjects genotyped as poor metabolizers of CYP2D6 at screening
  • Active smoking or use of CAF containing beverage (coffee, certain colas) for one week prior and during the study period due to known effects on CYP1A2 activity.
  • Subjects expressing inability to conform to dietary restrictions required for the study
  • The use of any illicit drugs or habitual consumption of large quantities of ethanol (> 3 drinks/day)
  Contacts and Locations
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Please refer to this study by its identifier: NCT00200798

Contact: John S. Markowitz, Pharm.D. 843-792-0172
Contact: Jennifer L. Donovan, Ph.D. 843-792-5589

United States, South Carolina
Medical University of South Carolina, GCRC Recruiting
Charleston, South Carolina, United States, 29425
Sub-Investigator: Jennifer L. Donovan, Ph.D.         
Sponsors and Collaborators
Medical University of South Carolina
National Center for Complementary and Integrative Health (NCCIH)
Office of Dietary Supplements (ODS)
Principal Investigator: John S. Markowitz, Pharm.D. Medical University of South Carolina
  More Information

Responsible Party: John S. Markowitz, Pharm.D., MUSC Identifier: NCT00200798     History of Changes
Other Study ID Numbers: R21AT002817-01 ( US NIH Grant/Contract Award Number )
Study First Received: September 13, 2005
Last Updated: December 9, 2009

Keywords provided by Medical University of South Carolina:
Milk Thistle
drug interactions
Normal volunteers processed this record on April 24, 2017