Healthy volunteers Levothyroxine absorption, Oral Administration, Sublingual Administration, Healthy Volunteers
Conditions
Interventions
Arm 1 Oral Levothyroxine
Participants will receive a single oral dose of Levothyroxine 4 mcg/kg administered with water after an overnight fast
No food will be allowed for at least 4 hours after drug
Active Comparator Drug,Active Comparator Drug
Oral administration,Sublingual administration
Sponsors
Siriraj Medical Research Center
Eligibility
Sex/Gender
All
Age
18 Years to 45 Years
Inclusion criteria
Inclusion criteria: 1. Age 18 to 45 years 2. Healthy volunteers with no history of thyroid disease 3. Normal thyroid function defined as TSH and Free T4 within reference range 4. No use of levothyroxine or other thyroid hormones within the past 3 months 5. No use of medications or supplements that affect levothyroxine absorption including aluminum containing antacids, sucralfate, cholestyramine, orlistat, proton pump inhibitors, phenytoin, carbamazepine, protease inhibitors, ciprofloxacin, raloxifene, rifampin, calcium, iron, or biotin 6. No known allergy to levothyroxine 7. Body Mass Index 18.5 to 30 kg per m2 8. Systolic blood pressure less than 140 mmHg and diastolic blood pressure less than 90 mmHg 9. Resting heart rate 60 to 100 beats per minute 10. Willing and able to provide written informed consent
Exclusion criteria
Exclusion criteria: 1. History of thyroid diseases such as hypothyroidism, hyperthyroidism, Graves disease, or Hashimoto thyroiditis 2. Conditions affecting drug absorption including chronic inflammatory bowel disease, celiac disease, or history of partial gastric bypass surgery 3. Severe liver disease or kidney disease that may alter drug metabolism 4. Pregnancy or breastfeeding 5. Use of medications that affect thyroid hormone such as corticosteroids, estrogen therapy, amiodarone, or lithium 6. Severe cardiovascular diseases including uncontrolled hypertension, arrhythmias, or ischemic heart disease 7. Heavy smoking or alcohol consumption more than 14 drinks per week in men or more than 7 drinks per week in women 8. Inability to comply with study protocol including fasting requirements or scheduled follow up visits
Design outcomes
Primary
| Measure | Time frame |
|---|---|
| Serum total thyroxine concentration and Serum free thyroxine concentration 0 hr 30 min 1 h 2 h 3 h 4 h blood samples | — |
Countries
Thailand
Contacts
Public ContactTada Kunavisarut
Faculty of Medicine Siriraj Hospital, Mahidol University
Outcome results
None listed