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LEVOTHYROXINE

Brand Name(s) : Eltroxin, Evotrox
Warnings
Uses
Side Effects
Precautions
Interactions
Overdose

LEVOTHYROXINE WARNINGS

Levothyroxine should be used with caution in: the elderly, those with diabetes or heart disease, including recent heart attack (myocardial infarction), angina (chest pain when the heart does not receive enough blood), high blood pressure (hypertension) and heart failure, those who have had hypothyroidism (under-active thyroid gland) for a long time and in pregnant women, those with any condition which affects the adrenal gland

It should not be used in: patients with an over-active thyroid gland, sometimes described as thyrotoxicosis or hyperthyroidism (a condition in which excessive amounts of thyroid hormone are produced)

Also see list of precautions and interactions

STORAGE

Store below 25°C

LEVOTHYROXINE USES

Levothyroxine is a synthetic form of the naturally occurring hormone thyroxine, produced by the thyroid gland.

It is a type of medicine termed a thyroid hormone, and is sometimes known as L-thyroxine or synthetic T4.

In general this drug is used to treat low levels of thyroxine (hypothyroidism), which can be associated with the following symptoms: tiredness, muscle weakness, cramps, feeling the cold, a slow heart rate, dry and flaky skin, hair loss, a deep husky voice and weight gain.

Benefits of taking this drug can include relief from the symptoms of hypothyroidism (or reduced thyroid gland size or prevention of an enlarged thyroid gland when taken to treat/prevent goitre).

Levothyroxine can also be used to treat or prevent goiter (an enlarged thyroid gland), which can be caused by hormone imbalances, radiation treatment, surgery or cancer.

Listed below are the typical uses of levothyroxine.

  • The treatment of an under-active thyroid gland (a condition known as hypothyroidism)
  • To treat or prevent goiter (an enlarged thyroid gland).

HOW TO USE/TAKE

How often do I take it?

  • This medication is available as a solution or as a tablet, either of which should be taken orally, usually once daily with a glass of water and before eating breakfast.
  • Use this medication regularly in order to get the most benefit from it.
  • Remember to use it at the same time each day - unless specifically told otherwise by your doctor.
  • It may take some weeks before the full benefit of this drug takes effect, depending on the dose given and the severity of the condition.
  • Certain medical conditions may require different dosage instructions as directed by your doctor.

What dose?

  • Dosage is based on your age, gender, medical condition, response to therapy, and use of certain interacting medicines.

Do I need to avoid anything?

  • You should not need to avoid any particular activities or foods when taking this medication. Consult your doctor or pharmacist for more details.

When can I stop?

  • It is important to continue taking this medication even if you feel well, unless your doctor tells you to stop.

LEVOTHYROXINE SIDE EFFECTS

If any of these persist or you consider them severe then inform your doctor.

Remember that your doctor has prescribed this medication because he or she has judged that the benefit to you is greater than the risk of side effects. Many people using this medication do not have serious side effects.

A serious allergic reaction to this drug is unlikely, but seek immediate medical attention if it occurs. Symptoms of a serious allergic reaction include: rash, itching/swelling (especially of the face/tongue/throat), dizziness, trouble breathing.

This is not a complete list of possible side effects. If you notice other effects not listed above, contact your doctor or pharmacist.

The Yellow Card Scheme allows you to report suspected side effects from any type of medicine (which includes vaccines, herbals and over the counter medicines) that you are taking. It is run by the medicines safety watchdog called the Medicines and Healthcare products Regulatory agency (MHRA). Please report any suspected side effect on the Yellow Card Scheme website.

LEVOTHYROXINE PRECAUTIONS

Before taking levothyroxine, tell your doctor or pharmacist if you are allergic to it; or to other thyroid hormones; or if you have any other allergies.

This medication should not be used if you have certain medical conditions. Before using this medicine, consult your doctor or pharmacist if you have: an over-active thyroid gland, sometimes described as thyrotoxicosis or hyperthyroidism.

Before using this medication, tell your doctor or pharmacist your medical history, especially any of the following: any conditions that might affect the adrenal gland (such as panhypopituitarism in which most of the hormones produced by the pituitary gland are not produced or produced in small quantities), any heart condition or suspected heart condition (including high blood pressure, previous heart attack), a history of diabetes or long-term, severe hypothyroidism (under-active thyroid gland).

Before having surgery, tell your doctor or dentist that you are taking this medication.

Does alcohol intake affect this drug?

  • Alcohol is not known to affect this drug.

The elderly: levothyroxine should be used with caution in the elderly as it may be started at a lower dose than in younger patients.

Pregnancy and breastfeeding - please ensure you read the detailed information below

PREGNANCY

Levothyroxine is suitable to take during pregnancy. Ask your doctor or pharmacist if you have any doubts or questions about this.

It is sensible to limit use of medication during pregnancy whenever possible. However, your doctor may decide that the benefits outweigh the risks in individual circumstances and after a careful assessment of your specific health situation.

If you have any doubts or concerns you are advised to discuss the medicine with your doctor or pharmacist.

BREAST FEEDING

Levothyroxine is suitable to take if you are breastfeeding.

Ask your doctor or pharmacist if you have any doubts or questions about this.

It is sensible to limit use of medication during breastfeeding whenever possible. However, your doctor may decide that the benefits outweigh the risks in individual circumstances and after a careful assessment of your specific health situation.

If you have any doubts or concerns you are advised to discuss the medicine with your doctor or pharmacist.

LEVOTHYROXINE INTERACTIONS

Your doctor or pharmacist may already be aware of any possible drug interactions and may be monitoring you for them. Do not start, stop, or change the dosage of any medicine before checking with them first.

Before using this medication, tell your doctor or pharmacist of all prescription and non-prescription/herbal products you may use, especially of:

  • Warfarin
  • Carbamazepine
  • Phenobarbital
  • Primidone
  • Phenytoin
  • Colestyramine
  • Ephedrine
  • Calcium carbonate
  • Rifampicin
  • Amitriptyline
  • Sertraline
  • Insulin
  • Gliclazide
  • Tolbutamide
  • Ketamine
  • Ferrous sulphate
  • Oestrogens
  • Androgens
  • Sucralfate
  • Digoxin
This information does not contain all possible interactions. Therefore, before using levothyroxine, tell your doctor or pharmacist of all the products you use.

LEVOTHYROXINE OVERDOSE

In most cases of overdose there will be no symptoms. In some cases symptoms of hyperthyroidism (excess thyroid hormone levels) may develop 3 to 6 days after overdose, such as changes in heart beat (which may become fast or irregular), tremor, inability to sleep (insomnia) and fever.

If you think you, or someone you care for, might have accidentally taken more than the recommended dose of levothyroxine or intentional overdose is suspected, contact your local hospital, GP or if in England call 111. In Scotland call NHS 24. In Wales, call NHS Direct Wales. In the case of medical emergencies, always dial 999.

MISSED DOSE

If you miss a dose, take it as soon as you remember. If it is near the time of the next dose, skip the missed dose and resume your usual dosing schedule. Do not double the dose to catch up.

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Source: Selected from data included with permission and copyrighted by Boots UK Limited or TicTac Communications Ltd. This copyrighted material is sourced from a licensed data provider and is not for distribution, except as may be authorised by the applicable terms of use.
CONDITIONS OF USE: The information in this database is intended to supplement, not substitute for, the expertise and judgement of healthcare professionals. The information is not intended to cover all possible uses, directions, precautions, drug interactions or adverse events, nor should it be construed to indicate that use of a particular medicine is safe, appropriate or effective for you or anyone else. A healthcare professional should be consulted before taking any medicine, changing any diet, or discontinuing any course of treatment.

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