Can Levothyroxine/ Thyrox can be taken at night?

Academic post:
”Can Levothyroxine/ Thyrox can be taken at night?”

  1. Levothyroxine/ Thyrox used to treat Hypothyroidism should be taken 30-60 minutes before breakfast.
  2. Drugs eg. Antacid, Calcium, Iron decrease Levothyroxine absorption so should be taken four hours after. Even PPI may impair absorption by decreasing gastric acid.
  3. Some patients think it inconvenient due to difficultly in waiting 30-60 minutes before breakfast.
  4. One study, reported in Journal of Clinical Endocrinology and Metabolism in 2009, examined impact on thyroid hormone tests after switching from early morning to bedtime and find even better correction of TSH at night doses may be due to slower bowel motility at night allowing better absorption of Levothyroxine!
  5. So Levothyroxine can be taken at night 4 hours after dinner with no interfering medication at night.
  6. In my practice, some patients mostly young doctors ask me about this. I ask them Sir, can you complete your dinner before sunset with no food/snacks or medications after this. In Bangladesh perspective, answer is always no.
  7. So practically its better to advise to take Levothyroxine/ Thyrox 30-60 minutes before breakfast for better absorption and consistency.

Dr. M Saifuddin
MBBS (DMC, K-56)
FCPS (Med), MD (Endo), FRCP (Ireland)
Assistant professor (Endocrinology)
Dhaka Medical College &
Author, FAQs in Diabetes, Endocrinology and Metabolism

Platform academic / Ariful Islam Neloy

Leave a Reply