Dosing of LT4 (DOT4)

Dosing of LT4 (DOT4)
Recruiting
65 years - 100 years
All
Phase N/A
228 participants needed
1 Location

Brief description of study

The purpose of this study is to find the effects of taking different doses of the thyroid medication levothyroxine in older people who already take levothyroxine for hypothyroidism.
Older people are more likely to have problems when their dose of levothyroxine is too strong. Allowing lower doses of levothyroxine would help prevent overmedicating older people with levothyroxine doses that are too strong. 

Detailed description of study

The study involves 3 in person visits at Penn Research Center, 4 or 5 visits to your local Penn lab, and receiving 4 phone calls from study staff over approximately 8 to 10 months.

Eligibility of study

You may be eligible for this study if you meet the following criteria:

  • Conditions: Endocrinology,Diabetes,Metabolism,EDM
  • Age: 65 years - 100 years
  • Gender: All

Inclusion
  • Adult 65 years or older, not in a nursing home
  • Hypothyroid (any type) for at least 6 months
  • Currently taking 75-200 mcg of levothyroxine (under any brand name) per day
  • Willing to adhere to study levothyroxine medication regimen
Exclusion
  • Currently taking liothyronine (LT3) or thyroid extracts
  • Currently taking amiodarone

Updated on 02 Jul 2025. Study ID: 23-0401

Pre-Screener

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Have you had a diagnosis of hypothyroidism for at least 6 months?

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