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Thyroid HealthThyroid Health

Thyroid medicines either replace missing hormone or reduce excess hormone production. Diagnosis and dose adjustments are guided by symptoms and blood tests.

Neomercazole

Carbimazole

5 · 10mg

Carbimazole 5mg and 10mg tablets, used in the management of hyperthyroidism. It blocks thyroid peroxidase, so T3 and T4 are not made.

From$0.21/ tabletView

Tapazole

Thiamazole

5 · 10mg

Thiamazole 5mg and 10mg tablets, used in the management of hyperthyroidism. A thionamide that blocks the enzyme thyroid peroxidase.

From$0.48/ tabletView

Cytomel

Liothyronine

20mcg

Cytomel is liothyronine 20mcg tablets for hypothyroidism, supplying the T3 thyroid hormone rather than the more usual T4 replacement.

From$0.94/ tabletView

Levothroid

Levothyroxine

25 · 50mcg

Levothyroxine 25mcg and 50mcg tablets, used in the management of hypothyroidism and thyroid-stimulating hormone suppression. Synthetic T4.

From$0.15/ tabletView

Key points

  • Levothyroxine is replacement treatment for an underactive thyroid; liothyronine has a more limited, specialist-directed role.
  • Carbimazole and thiamazole reduce thyroid hormone production and require monitoring for uncommon but serious adverse effects.
  • Switching product, changing dose or stopping treatment without review can destabilise thyroid control.

Listings are for comparison only; suitability and supply depend on clinician and pharmacy checks, blood-test results and prescription requirements.

How the medicine groups differ

Thyroid replacement includes levothyroxine and, in selected cases, liothyronine. Antithyroid medicines include carbimazole and thiamazole. Replacement and antithyroid medicines treat opposite hormone problems and are not substitutes for one another.

What these medicines are used for

Replacement medicines are used for hypothyroidism. Antithyroid medicines may be used for hyperthyroidism as part of a clinician-led plan.

Important safety checks

Tell the clinician about pregnancy or plans for pregnancy, heart disease and all medicines or supplements. Iron, calcium and some other products can affect thyroid hormone absorption. Blood tests are needed after relevant treatment changes; symptoms alone cannot confirm the correct dose.

When to seek urgent care

While taking an antithyroid medicine, fever, sore throat or mouth ulcers require urgent medical advice and a blood-count check. Seek emergency help for chest pain, severe breathlessness, fainting, marked confusion, a very fast or irregular heartbeat, or a serious allergic reaction.

Further reading

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