The Effect of Coffee on the Absorption of Thyroid Hormone in Patients With Thyroid Carcinoma
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|ClinicalTrials.gov Identifier: NCT01707056|
Recruitment Status : Unknown
Verified May 2013 by Washington Hospital Center.
Recruitment status was: Recruiting
First Posted : October 15, 2012
Last Update Posted : May 22, 2013
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.
|Condition or disease||Intervention/treatment||Phase|
|Thyroid Carcinoma Hypothyroidism||Other: Black Coffee Other: Coffee with Milk Other: Black Tea Other: Water||Not Applicable|
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 (Clinical Trial)|
|Estimated Enrollment :||10 participants|
|Intervention Model:||Crossover Assignment|
|Masking:||None (Open Label)|
|Official Title:||The Effect of Coffee Consumption on the Intestinal Absorption of Levothyroxine Thyroid Hormone Replacement in Patients With Thyroid Carcinoma|
|Study Start Date :||September 2012|
|Estimated Primary Completion Date :||June 2015|
|Estimated Study Completion Date :||June 2016|
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.
Taking Synthroid with water for a period of 6 weeks.
- Change in TSH (thyrotropin-stimulating-hormone) with each beverage type [ Time Frame: 6 hours ]
- change in TSH over 6 hours
- peak change in TSH over 6 hours
- 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.
- Change in total T4 with each beverage type [ Time Frame: 6 hours ]
- Change in total T4 over 6 hours
- Peak change in total T4 over 6 hours
- area under the curve (AUC) for total T4
- Change in free T4 with each beverage type [ Time Frame: 6 hours ]
- Change in free T4 over 6 hours
- Peak change in free T4 over 6 hours
- area under the curve (AUC) for free T4
- Change in total T3 with each beverage type [ Time Frame: 6 hours ]
- Change in total T3 over 6 hours
- Peak change in total T3 over 6 hours
- area under the curve (AUC) for total T3
To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.
Please refer to this study by its ClinicalTrials.gov identifier (NCT number): NCT01707056
|Contact: Dorota Krajewski, MD||(301) email@example.com|
|Contact: Jaqueline Jonklaas, MD||(202) firstname.lastname@example.org|
|United States, District of Columbia|
|Georgetown University Hospital||Recruiting|
|Washington, District of Columbia, United States, 20007|
|Contact: Jacqueline Jonklaas, MD 202-687-2818 email@example.com|
|Principal Investigator: Jacqueline Jonklaas, MD|
|Washington Hospital Center||Recruiting|
|Washington, District of Columbia, United States, 20010|
|Contact: Kenneth D Burman, MD 202-877-6563 Kenneth.firstname.lastname@example.org|
|Principal Investigator: Kenneth D Burman, MD|
|United States, Maryland|
|MedStar St. Mary's Hospital||Recruiting|
|Leonardtown, Maryland, United States, 20650|
|Contact: Dorota A Krajewski, MD 301-475-7750 email@example.com|
|Principal Investigator: Dorota A Krajewski, MD|
|Principal Investigator:||Dorota Krajewski, MD||Medstar|