Thyroid hormone replacement
Last reviewed June 2026
Who is this for?
Levothyroxine is a man-made version of the thyroid hormone that your body normally produces. It works by replacing or topping up the thyroid hormone when your thyroid gland (a small gland in your neck) is not making enough on its own.
Binds to thyroid hormone receptors (TRα and TRβ) in target tissues, activating gene transcription and increasing cellular metabolic rate, oxygen consumption, and heat production to restore normal thyroid hormone levels in hypothyroid states.
Prescription Required
You need a doctor's prescription to buy this drug.
Explore this drug
Take one tablet once a day in the morning on an empty stomach, at least 30 to 60 minutes before eating breakfast. Swallow the tablet with a full glass of water. Your doctor will start you on a low dose (usually 25-50 mcg) and gradually increase it based on your blood test results. Do not stop taking it or change your dose without your doctor's approval — most people take this medicine for life.
If you miss a dose, take it as soon as you remember that same day. If you don't remember until the next day, skip the missed dose and take your normal dose — do not take two tablets at once to make up for it.
Always buy from a licensed pharmacy — do not purchase from roadside vendors or unverified online sellers, as fake thyroid medicines are dangerous. This is a lifelong medicine for most people, so do not stop taking it because you feel better — your symptoms will return. Attend your regular blood tests (thyroid function tests) so your doctor can make sure your dose is correct.
Calcium or iron supplements and antacids (like aluminium or magnesium-containing medicines) can stop levothyroxine from working properly — take them at least 4 hours apart. Warfarin (blood thinner) effects may increase, so your doctor may need to adjust your warfarin dose. Diabetes medicines (including insulin and metformin) may need dose adjustment because levothyroxine can affect blood sugar levels.
Check your specific combination
Is it safe to take Levothyroxine with your other drugs?
Levothyroxine is generally safe to continue during pregnancy and breastfeeding — in fact, it is very important for both mother and baby that thyroid levels stay normal, but your doctor may need to adjust your dose, so inform them as soon as you know you are pregnant.
Store in a cool, dry place away from direct sunlight and heat — this is especially important in hot Nigerian weather. Keep the tablets in their original pack and away from moisture. Always keep out of reach of children.
For information only — not medical advice. Always talk to a doctor or pharmacist before changing your medication.
Names this drug is sold under — especially in Nigerian and West African pharmacies
Tap a brand for packaging, NAFDAC details and authenticity check
Counterfeit Drug Warning
Fake drugs are a serious problem in Nigeria. Always buy from a registered pharmacy. If the packaging looks different from what is described above, do not use it.
Dispensing Levothyroxine Sodium?
Clinical tools built for Nigerian pharmacists — launching soon.