Levothyroxine (Thyroxine) 100 mcg: uses, price & cheaper substitutes
Prescription required (Schedule H)
Common uses: Hypothyroidism – an underactive thyroid gland, when a higher maintenance dose is needed; Replacement after thyroid surgery or radio-iodine treatment.
Listed MRPs range from ₹0.64 to ₹1.42 per tablet across 6 listings. Use only on a doctor's prescription.
Price comparison
| Brand | Manufacturer | Pack | MRP | ₹ / tablet | As on |
|---|---|---|---|---|---|
| Thyroxine Sodium Tablets IP 100 mcgJan Aushadhi | Jan Aushadhi (PMBJP) | 100 | ₹63.94 | ₹0.64 | 19 October 2026 |
| Thyroxinol 100 | Knoll Pharmaceuticals Ltd | 120 | ₹166.10 | ₹1.38 | 19 October 2026 |
| Thyronorm 100 | Abbott | 120 | ₹169.91 | ₹1.42 | 19 October 2026 |
| Eltroxin 100 | Glaxo SmithKline Pharmaceuticals Ltd | 120 | ₹169.93 | ₹1.42 | 19 October 2026 |
| Thyrox 100 | Macleods Pharmaceuticals Pvt Ltd | 120 | ₹169.92 | ₹1.42 | 19 October 2026 |
| Lethyrox 100 | Intas Pharmaceuticals Ltd | 120 | ₹170.10 | ₹1.42 | 19 October 2026 |
MRPs as printed/listed on the date shown; actual price may vary.
Uses
- Hypothyroidism – an underactive thyroid gland, when a higher maintenance dose is needed.
- Replacement after thyroid surgery or radio-iodine treatment.
- Hashimoto's thyroiditis with low thyroid hormone.
- TSH suppression after thyroid cancer surgery, under specialist care.
How to take it
Take one tablet every morning on an empty stomach, 30 to 60 minutes before breakfast, with plain water only. Keep a 4-hour gap from iron, calcium, antacids and multivitamins. 100 mcg is a common maintenance dose; it is set from your TSH level and weight by your doctor, who rechecks TSH 6 to 8 weeks after any change. Do not change the dose or brand yourself.
Side effects
Common
- Symptoms of too much hormone if the dose is high: palpitations, sweating, heat intolerance.
- Weight loss, increased appetite.
- Anxiety, insomnia, tremor.
- Headache.
- Diarrhoea.
Serious
Stop and get medical help urgently if you notice any of these.
- Chest pain, very fast or irregular heartbeat.
- Long-term over-replacement – bone thinning (osteoporosis), atrial fibrillation.
- Severe allergic reaction (rare).
- In children, growth and behaviour effects if the dose is too high.
Safety information
Alcohol
No direct interaction; keep alcohol moderate and away from the tablet time.
Pregnancy
Safe and necessary in pregnancy if you are hypothyroid. Tell your doctor immediately when pregnant – the dose usually needs to increase and TSH is checked every trimester. Safe in breastfeeding.
Kidney problems
No dose change needed.
Liver problems
No dose change usually needed.
Children
Children use weight-based doses set by a paediatric endocrinologist; 100 mcg may be too much for a small child.
Missed dose
Take it as soon as you remember the same day on an empty stomach. If you remember only the next day, take two tablets that morning and then continue as usual. Avoid repeated misses.
Interactions
- Iron, calcium, antacids, sucralfate, soya – reduce absorption; keep a 4-hour gap.
- Proton pump inhibitors (pantoprazole, omeprazole) – may reduce absorption over time.
- Warfarin – anticoagulant effect increases.
- Diabetes medicines – blood sugar control may change.
- Carbamazepine, phenytoin, rifampicin – increase levothyroxine breakdown.
- Oestrogen pills or HRT – may raise the dose you need.
- Coffee and tea with the tablet reduce absorption.
Frequently asked questions
Thyronorm 100 empty stomach – how long before food?
Take it 30 to 60 minutes before breakfast or tea with plain water. Food, milk and coffee reduce absorption and make your TSH unstable.
Is 100 mcg a high dose of thyroxine?
No, 100 mcg is a common full-replacement dose for an adult; typical needs are about 1.6 mcg per kg of body weight. Your doctor sets it from your TSH, not from how it sounds.
Can I take Thyronorm 100 at night instead?
Yes, bedtime dosing at least 3 hours after dinner is an accepted alternative. Keep the same routine every day and recheck TSH after any change in timing.
Can I take Thyronorm 100 with alcohol?
There is no direct interaction, but keep alcohol moderate and never with the tablet.
Thyronorm 100 vs Eltroxin 100 – can I switch?
Both are levothyroxine 100 mcg, but absorption can differ slightly between brands. If you switch, tell your doctor and recheck TSH in 6 to 8 weeks.
Is Thyronorm 100 safe in pregnancy?
Yes and essential. Many women need a 25 to 30 percent dose increase in pregnancy. See your doctor as soon as you know you are pregnant.
What if I take two Thyronorm 100 tablets by mistake?
A single double dose is unlikely to cause harm because thyroxine builds up slowly. Skip the next day's dose and continue normally. Repeated overdosing causes palpitations and other problems – see a doctor if you have symptoms.
Does Thyronorm 100 need a prescription?
Yes. Levothyroxine is a Schedule H medicine in India and the dose must be guided by blood tests.
Sources
- NHS – Levothyroxine (19 October 2026)
- MedlinePlus – Levothyroxine (19 October 2026)
- NPPA Pharma Sahi Daam (ceiling prices) (19 October 2026)
- PMBI Jan Aushadhi Product & MRP List (19 October 2026)
Medyzen Editorial Team · Last updated
This page is general information, not medical advice. Do not start, stop or change a medicine without asking a doctor or pharmacist. Terms