Liothyronine - oral

Patient Medicine Information
Why do I need this medicine?
Liothyronine is used to treat the abnormally low activity of the thyroid gland. It replaces or adds on to the natural thyroid hormones normally produced by the thyroid gland. Thyroid hormones help in many body functions related to growth and energy.

This medicine is also used as an aid in thyroid function test.
How do I take this medicine?
Take Liothyronine exactly as directed by your doctor or according to the instructions on the label. Do not take more or less than instructed by your doctor.

You may take this medicine with or without food. Try to take it at the same time each day.

Liothyronine must be taken regularly for it to be effective. Continue taking this medicine even when you feel better. Do not stop taking it unless instructed by the doctor.
What should I do if I have forgotten to take this medicine?
Take the missed dose as soon as you remember. If it is almost time for your next dose, skip the missed dose and return to your normal dosing schedule.

DO NOT double a dose under any circumstances.

If you often forget to take your medicine, let your doctor and pharmacist know.
When should I not use this medicine?
Alert your doctor if you have the following conditions:
  • untreated overactive thyroid
  • uncorrected adrenal insufficiency (a disorder of adrenal glands where it doesn’t produce sufficient hormones)
  • chest pain or recent heart attack
as Liothyronine may not be suitable for you.
What should I take note of while taking this medicine?
Inform your doctor if you have the following conditions:
  • adrenal gland disorder
  • severe and long-standing hypothyroidism (low activity of thyroid gland)
  • diabetes
  • heart disease
  • kidney disease
Let your doctor know if you are pregnant or breastfeeding.

Be sure to check with your doctor or pharmacist before giving Liothyronine to a child or the elderly. Children and elderly people may be more sensitive to the side effects.

Do not switch brands unless instructed by your doctor. This is because different brands of Liothyronine may have slightly different ways of working in your body.

Keep your appointments with your doctor. Your doctor needs to monitor your condition and check your response to the medication regularly. Regular monitoring of thyroid hormone levels, blood pressure, heart rate, blood sugar and kidney function may also be needed. Your doctor will advise you about how often you need to have these tests.
What side effects could I experience?
Liothyronine may cause any of the following side effects: headache, diarrhoea, vomiting, abdominal cramps, weight loss, muscle weakness, anxiety, inability to tolerate heat, irregular menstruation, problems falling asleep, and fever.

Some side effects may need immediate medical help. Alert your doctor quickly if you experience any of the following
  • chest pain, fast or irregular heartbeat
  • breathlessness, excessive sweating, increased anxiety, agitation or lethargy
Inform your doctor if any of these side effects do not go away or are severe, or if you experience other side effects.
Can I take this with other medicines?
Inform your doctor and pharmacist if you are taking or using any of these medicines:
  • medicines for epilepsy (seizures or fits) e.g. phenytoin, carbamazepine, phenobarbital
  • medicines for diabetes e.g. insulin, metformin, gliclazide
  • medicines for irregular heartbeat e.g. digoxin, amiodarone
  • medicines for high blood pressure e.g. propranolol
  • medicines for depression e.g. amitriptyline, imipramine, sertraline
  • cholesterol-lowering medicines known as bile acid sequestrant e.g. colestyramine, colestipol
  • rifampicin (medicine to treat a lung infection known as TB)
  • ketamine (medicine to block pain and sensation)
  • blood-thinning medicines e.g. coumarin, phenindione
This list does not include all medicines that may interact with Liothyronine.

Inform your doctor if you are currently taking birth control pills as this can reduce the effectiveness of Liothyronine. You should not stop or start any birth control pills without first informing your doctor. Ask your doctor about using non-hormonal birth control as an alternative while being treated with this medicine.

Always notify your doctor and pharmacist if you are taking any other medicines, including herbal tonics, such as traditional Chinese medicines, supplements and medicines that you buy without a prescription.
What special dietary instructions should I follow?
Avoid alcohol.
How should I store this medicine?
Store in a cool, dry place away from the reach of children.

Medicines must not be used past the expiry date.
This information is independently developed by MIMS based on liothyronine - oral and is provided for your reference only. It is not a replacement for and should only be used in conjunction with full consultation with a licensed healthcare professional, the information provided by your pharmacist and/or the manufacturer of the medication. It may not contain all the available information you require and cannot substitute professional medical care, nor does it take into account all individual circumstances. Although great effort has been made to ensure content accuracy, we shall not be held responsible or liable for any claims or damages arising from the use or misuse of the information contained herein, its contents or omissions, or otherwise. Copyright © 2021 MIMS. All rights reserved. Powered by
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