Levothyroxine
Also known as: Thyroxine, T4
Levothyroxine replaces missing thyroid hormone in hypothyroidism and is usually taken for life.
Common brands
- Thyronorm
- Eltroxin
- Thyrox
Dosage forms
- Tablet
Uses
- Hypothyroidism
- After thyroid surgery
How it works
Replaces the thyroid hormone T4.
How to take
Take on an empty stomach in the morning, 30-60 minutes before breakfast or tea; keep timing consistent.
Common side effects
- Usually none at the right dose
Serious side effects — get medical help
- Palpitations, tremor or weight loss if dose too high
Who should not take it
- Untreated adrenal insufficiency
Interactions
- Calcium, iron and antacids (take 4 hours apart)
- Soy, coffee
Pregnancy & breastfeeding
Safe and important in pregnancy; dose often needs to increase.
Alcohol & driving
No specific restriction.
Storage
Store below 25°C, protected from light and moisture.
Used for these conditions
Prescribed by
Brands available in India
Frequently asked questions
What is Levothyroxine used for?
Hypothyroidism, After thyroid surgery
What are the side effects of Levothyroxine?
Usually none at the right dose
How should I take Levothyroxine?
Take on an empty stomach in the morning, 30-60 minutes before breakfast or tea; keep timing consistent.
Who should not take Levothyroxine?
Untreated adrenal insufficiency
Medically reviewed by
Medical review pending
Last updated
9 October 2026
Sources
- National List of Essential Medicines (NLEM) 2022, MoHFW
- National Formulary of India, Indian Pharmacopoeia Commission
- CDSCO approved drug information
This information is for general awareness and does not replace advice from a qualified doctor. Do not start, stop or change any medicine without medical advice.