Clinical Evaluation of the Pharmacokinetic Goldenseal-Metformin Interaction in Diabetic Patients
Interaction, Adverse Herb-Drug, Diabetes Mellitus, Type 2
About this trial
This is an interventional basic science trial for Interaction, Adverse Herb-Drug focused on measuring pharmacokinetics, natural product-drug interactions, transporters
Eligibility Criteria
Inclusion Criteria:
- are 18-65 years old and healthy
- have been medically diagnosed with Type 2 diabetes and currently taking metformin (1- 2 g daily), but otherwise healthy as determined by the study physician
- have an HbA1c < 8% as determined by laboratory analysis on initial screening
- are not taking any medications, dietary/herbal supplements, or citrus juices that can interfere with your ability to eliminate the study drugs and goldenseal from your body
- are willing to stop consuming alcohol, caffeinated beverages or other caffeine- containing products the evening before and the morning of the first day of each study arm
- are female and are willing to use an acceptable method of birth control that does not include oral birth control pills or patches (such as abstinence, copper IUD, condom)
- can provide written informed consent (and assent when applicable) obtained from subject or subject's legal representative and ability for the subject to comply with the requirements of the study
Exclusion Criteria:
- have an HbA1c ≥ 8%
- have other chronic illnesses other than type 2 diabetes (e.g., type 1 diabetes, kidney disease, hepatic disease, uncontrolled hypertension, coronary artery disease, chronic obstructive pulmonary disease, cancer, or HIV/AIDS)
- have a hematologic (blood) disorder
- have a history of drug or alcohol abuse
- have any major psychiatric illness
- are pregnant or breastfeeding
- have a history of intolerance or allergy to midazolam or goldenseal products
- are taking concomitant medications, both prescription and non-prescription (including dietary supplements/herbal products) known to alter the pharmacokinetics of either study drug or goldenseal constituents
Sites / Locations
- Washington State University College of Pharmacy and Pharmaceutical Sciences
Arms of the Study
Arm 1
Arm 2
Arm 3
Experimental
Experimental
Experimental
Study Arm 1: Baseline
Study Arm 2: Acute Goldenseal Exposure
Study Arm 3: Chronic Goldenseal Exposure
Twenty type 2 diabetic subjects (10 men, 10 women) will be administered a single dose of midazolam (0.5 mg) intravenously via a peripherally inserted catheter in conjunction with their daily oral administration of metformin. Plasma and urine will be collected from 0-24 hours post-midazolam administration. Participants will take their metformin as prescribed for the entirety of the study with no interruption in pharmacotherapy.
For Arm 2, the same 20 subjects will be administered a single dose of goldenseal (3.3 g) orally 30 minutes prior to administration of midazolam (as described in Arm 1). Plasma and urine will be collected in a manner identical to that in Arm 1. With respect to midazolam administration, a washout period of 7 days will separate Arm 2 from Arm 1.
For Arm 3, the same 20 subjects will be administered goldenseal (1.1 g) orally three times daily for 27 days. On the 28th day, participants will be administered the goldenseal three times daily, as well as the single dose of midazolam (as described in Arm 1). Plasma and urine will be collected in a manner identical to that in Arm 1. A designated washout period for midazolam will not be necessary to separate Arm 3 from Arm 2 since there will be 27 days of goldenseal administration prior to the midazolam administration.