The Effect of Coffee on the Absorption of Thyroid Hormone in Patients With Thyroid Carcinoma

February 15, 2021 updated by: Medstar Health Research Institute

The Effect of Coffee Consumption on the Intestinal Absorption of Levothyroxine Thyroid Hormone Replacement in Patients With Thyroid Carcinoma

The purpose of this study is to evaluate whether taking thyroid hormone medication with beverages other than water, decreases absorption of the medication by the intestine. Specifically we are interested in whether coffee, coffee with milk, or black tea affects how thyroid medication is absorbed by the body. Previous studies have suggested that taking thyroid hormone with coffee may interfere with the ability to absorb thyroid medicine. Given that many patients take their thyroid medicine with beverages other than water, and specifically with coffee or tea, understanding whether and how much coffee or tea may decrease thyroid hormone absorption is important for clinical practice.

This study will help determine the safest and most effective way for adults to take their thyroid medication and will guide medical practitioners in how to counsel their patients when they prescribe thyroid hormone.

Study Overview

Status

Withdrawn

Conditions

Intervention / Treatment

Detailed Description

Previous studies have suggested that taking thyroid replacement therapy with coffee potentially hinders its absorption. We already know that food especially a fiber-rich diet, cholestyramine resin, aluminum containing antacids, activated charcoal, and certain herbal remedies among others interfere with the ability to absorb thyroid medicine. These findings have prompted providers to advise patients to take their levothyroxine on an empty stomach in the morning. However, many patients take their thyroid medicine with their morning cup of coffee prior to eating breakfast. A small study has shown that Italian espresso coffee can decrease the absorption of levothyroxine, but the effect of American style coffee is not known. Given that the intestinal absorption of levothyroxine can be hindered by multiple substances and coffee is the most commonly consumed beverage worldwide, it is important to investigate what effect coffee may have on thyroid hormone absorption and thyroid function tests.

Using methods similar to those used in previous studies, this study will measure thyroid function tests in approximately 10-20 subjects (18-60 years of age) over a 6 hour period of time after taking their thyroid medication with the specified study beverage for a 6 week period. Subjects will be randomized to water, black coffee, coffee with milk, and black tea as four specified study beverages, with water serving as the control beverage. Each subject will be recruited to participate with each study beverage for a 6 week period of time in a total of four consecutive 6 week periods. Blood draws will occur at the end of each 6 week period on test days 1, 2, 3, and 4. The coffee will represent the most common household coffee brand, Folgers. Thyroid function tests with each beverage will be compared to thyroid function tests with water to determine if thyroid medication absorption is impaired by coffee, coffee with milk, or tea.

This study will help determine the safest and most efficacious way for adults to take their thyroid medication and will guide medical practitioners in how to counsel their patients when they prescribe thyroid replacement therapy.

Study Type

Interventional

Phase

  • Not Applicable

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Locations

  • United States
    • District of Columbia
      • Washington, District of Columbia, United States, 20010
        • Washington Hospital Center
      • Washington, District of Columbia, United States, 20007
        • Georgetown University Hospital
    • Maryland
      • Leonardtown, Maryland, United States, 20650
        • MedStar St. Mary's Hospital

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

18 years to 60 years (Adult)

Accepts Healthy Volunteers

No

Genders Eligible for Study

All

Description

Inclusion Criteria:

- patients with thyroid carcinoma after standard care of treatment on stable dose of Synthroid with a detectable baseline TSH

Exclusion Criteria:

  • Pregnancy
  • Undetectable baseline TSH
  • Not willing to drink coffee, coffee with milk, or black tea
  • Age less than 18 or greater than 60 years old
  • Taking generic thyroid hormone (levothyroxine) and not brand-name Synthroid
  • Dose of thyroid medication has been recently changed (less than 3 months ago)
  • Currently receiving treatment for gastroesophageal reflux disease, gastritis, stomach or intestinal cancer, inflammatory bowel disease, or H. pylori
  • Taking cholestyramine resin, colestipol hydrochloride, sucralfate, iron sulphate, aluminum containing antacids, activated charcoal, raloxifene, and herbal remedies
  • History of previous gastric or small intestine surgery
  • Diagnosis of kidney or liver disease, congestive heart failure, anemia, biliary disease, pancreatitis

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

  • Primary Purpose: Treatment
  • Allocation: Randomized
  • Interventional Model: Crossover Assignment
  • Masking: None (Open Label)

Arms and Interventions

Participant Group / Arm
Intervention / Treatment
Active Comparator: Black coffee
Synthroid will be administered with 12 ounces of black coffee for a period of 6 weeks.
Other: Black Coffee
Taking Synthroid with 12 ounces of black coffee for 6 weeks.
Active Comparator: Coffee with Milk
Synthroid will be administered with 12 ounces of coffee and 2 ounces of 2% milk for a period of 6 weeks.
Other: Coffee with Milk
Taking Synthroid with 12 ounces of black coffee and 2 ounces of 2% milk for a period of 6 weeks.
Active Comparator: Black Tea
Synthroid will be administered with 12 ounces of black Lipton tea for a period of 6 weeks.
Other: Black Tea
Taking Synthroid with 12 ounces of black tea for a period of 6 weeks.
Placebo Comparator: Water
Synthroid will be administered with 12 ounces of water for a period of 6 weeks.
Other: Water
Taking Synthroid with water for a period of 6 weeks.

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Change in TSH (thyrotropin-stimulating-hormone) with each beverage type
Time Frame: 6 hours
  1. change in TSH over 6 hours
  2. peak change in TSH over 6 hours
6 hours

Secondary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Change in TSH with various beverages
Time Frame: 6 weeks
To determine if taking Synthroid for 6 weeks with each of the prescribed study beverages results in a different baseline TSH, reflecting altered absorption of levothyroxine with each particular beverage.
6 weeks
Change in total T4 with each beverage type
Time Frame: 6 hours
  1. Change in total T4 over 6 hours
  2. Peak change in total T4 over 6 hours
  3. area under the curve (AUC) for total T4
6 hours
Change in free T4 with each beverage type
Time Frame: 6 hours
  1. Change in free T4 over 6 hours
  2. Peak change in free T4 over 6 hours
  3. area under the curve (AUC) for free T4
6 hours
Change in total T3 with each beverage type
Time Frame: 6 hours
  1. Change in total T3 over 6 hours
  2. Peak change in total T3 over 6 hours
  3. area under the curve (AUC) for total T3
6 hours

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Sponsor

Medstar Health Research Institute

Collaborators

Georgetown University

Investigators

  • Principal Investigator: Dorota Krajewski, MD, Medstar

Publications and helpful links

The person responsible for entering information about the study voluntarily provides these publications. These may be about anything related to the study.

General Publications

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Actual)

September 1, 2012

Primary Completion (Anticipated)

June 1, 2015

Study Completion (Anticipated)

June 1, 2016

Study Registration Dates

First Submitted

October 5, 2012

First Submitted That Met QC Criteria

October 12, 2012

First Posted (Estimate)

October 15, 2012

Study Record Updates

Last Update Posted (Actual)

February 17, 2021

Last Update Submitted That Met QC Criteria

February 15, 2021

Last Verified

February 1, 2021

More Information

Terms related to this study

Keywords

Additional Relevant MeSH Terms

Other Study ID Numbers

  • 2011-338

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

Clinical Trials on Hypothyroidism

Clinical Trials on Black Coffee

Search Similar Trials

Sponsors and Collaborators

Medical Conditions

Drug Interventions

CROs by country

CROs in Portugal

Conditions

Rare Diseases

Drug Interventions

Dietary Supplements

Sponsor/Collaborators

Locations

3
Subscribe