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THYROFIX 13 micrograms tablets

THYROFIX 13 micrograms tablets

This page is for general information. Consult a doctor for personal advice. Call emergency services if symptoms are severe.
About the medicine

How to use THYROFIX 13 micrograms tablets

Introduction

Package Leaflet: Information for the User

Thyrofix 13 micrograms tablets

Thyrofix 25 micrograms tablets EFG

Thyrofix 50 micrograms tablets EFG

Thyrofix 62 micrograms tablets

Thyrofix 75 micrograms tablets EFG

Thyrofix 88 micrograms tablets EFG

Thyrofix 100 micrograms tablets EFG

Thyrofix 112 micrograms tablets EFG

Thyrofix 125 micrograms tablets EFG

Thyrofix 137 micrograms tablets EFG

Thyrofix 150 micrograms tablets EFG

Thyrofix 175 micrograms tablets EFG

Thyrofix 200 micrograms tablets EFG

Levothyroxine sodium

Read the entire package leaflet carefully before starting to take this medication, as it contains important information for you.

  • Keep this package leaflet, as you may need to read it again.
  • If you have any doubts, consult your doctor or pharmacist.
  • This medication has been prescribed to you only, and you should not give it to others, even if they have the same symptoms as you, as it may harm them.
  • If you experience any type of adverse effect, consult your doctor or pharmacist, even if it is a possible adverse effect not listed in this package leaflet. See section 4.

Package Leaflet Contents:

  1. What is Thyrofix and what is it used for
  2. What you need to know before taking Thyrofix
  3. How to take Thyrofix
  4. Possible side effects
  5. Storage of Thyrofix
  6. Package Contents and Additional Information

1. What is Thyrofix and what is it used for

Levothyroxine, the active substance in this medication, is a synthetic thyroid hormone used to treat diseases and dysfunctions of the thyroid gland. It has the same effect as the natural hormone produced in the thyroid gland.

This medication is used to:

  • treat benign goiter in patients with normal thyroid function,
  • prevent the recurrence of goiter after surgery,
  • replace natural thyroid hormones when the thyroid gland does not produce them in sufficient quantities,
  • stop the growth of tumors in patients with thyroid cancer,

Thyrofix 13 micrograms, 25 micrograms, 50 micrograms, 62 micrograms, 75 micrograms, 88 micrograms, and 100 micrograms will also be used to balance thyroid hormone levels when hyperthyroidism is treated with antithyroid medications.

Thyrofix 75 micrograms, 100 micrograms, 150 micrograms, and 200 micrograms will also be used for thyroid function tests.

2. What you need to know before taking Thyrofix

Do not take Thyrofix if you have any of the following conditions:

  • allergy (hypersensitivity) to the active ingredient or any of the other components of this medication (listed in section 6),
  • untreated adrenal gland, pituitary gland, or excessive thyroid hormone overproduction (thyrotoxicosis),
  • acute heart disease (myocardial infarction or heart inflammation).

Do not take Thyrofix with antithyroid medications if you are pregnant (see Pregnancy and Breastfeeding section later).

Warnings and Precautions

Consult your doctor or pharmacist before taking this medication if you have any of the following heart conditions:

  • insufficient blood flow in the heart's blood vessels (angina pectoris),
  • heart failure,
  • rapid and irregular heartbeats,
  • high blood pressure,
  • fat deposits in your arteries (arteriosclerosis).

These conditions should be under medical control beforeyou start taking this medication or before undergoing a thyroid suppression test. You mustundergo frequent checks of your thyroid hormone levels while taking this medication. If you are unsure whether you have any of the described conditions or if you are not receiving treatment, contact your doctor.

Your doctor will investigate whether you have adrenal gland or pituitary gland dysfunction or uncontrolled thyroid gland dysfunction with excessive thyroid hormone production (thyroid autonomy), as this must be medically controlled before starting treatment or before undergoing a thyroid suppression test.

Blood pressure will be periodically monitored when starting treatment with levothyroxine in premature newborns with very low birth weight, as a rapid drop in blood pressure (known as circulatory collapse) may occur.

If you need to change your medication to another one containing levothyroxine, a thyroid imbalance may occur. Talk to your doctor if you have any doubts about changing your medication. During the transition period, close monitoring (clinical and biological) is required. You should tell your doctor if you experience any adverse effects, as this may indicate that your dose needs to be adjusted by increasing or decreasing it.

Talk to your doctor:

  • if you are menopausal or postmenopausal; your doctor may need to monitor your thyroid function due to the risk of osteoporosis,
  • before starting or stopping orlistat treatment, or changing orlistat treatment (a medication used to treat obesity, you may require more frequent monitoring and dose adjustment),
  • if you experience signs of psychotic disorders (you may require more frequent monitoring and dose adjustment),
  • if you are going to undergo laboratory tests to check your thyroid hormone levels, you should inform your doctor or laboratory staff that you are taking or have recently taken biotin (also known as vitamin H, vitamin B7, or vitamin B8). Biotin can affect laboratory test results. Depending on the test, the results may be falsely elevated or falsely reduced due to biotin. Your doctor may instruct you to stop taking biotin before undergoing the tests. You should also be aware that other products you may be taking, such as multivitamins or supplements for hair, skin, and nails, may also contain biotin. This could affect laboratory test results. Inform your doctor or laboratory staff if you are taking these products (see the information in the Other Medications and Thyrofix section).

The treatment with thyroid hormones is not indicated for weight loss. Taking thyroid hormones will not reduce your weight if your thyroid hormone levels are within the normal range. If you increase the dose, especially without consulting your doctor, you may experience serious or even life-threatening side effects. You should not take high doses of thyroid hormones with certain weight loss medications, such as amfepramone, catherine, and phenylpropanolamine, as this may increase the risk of serious side effects and even life-threatening effects.

Other Medications and Thyrofix

Inform your doctor or pharmacist if you are taking, have recently taken, or may need to take any of the following medications, as Thyrofix may affect their effect:

  • Medications for diabetes (medications that lower blood sugar levels):

This medication may reducethe effect of the medications you take to control diabetes, so you may need to undergo additional checks of your blood sugar levels, especially at the start of treatment. While taking Thyrofix, you may need to adjust the dose of your diabetes medication.

  • Coumarin derivatives (medications used to prevent blood clots):

Thyrofix may intensifythe effect of these medications, which may increase the risk of bleeding events, especially in elderly patients. When starting and during treatment with Thyrofix, you may need to frequently check your blood coagulation values. While taking Thyrofix, you may need to adjust the dose of coumarin you take.

  • Proton pump inhibitors: Proton pump inhibitors (such as omeprazole, esomeprazole, pantoprazole, rabeprazole, and lansoprazole) are used to reduce the amount of acid produced by the stomach, which may reduce the intestinal absorption of levothyroxine and, therefore, make it less effective. If you are taking levothyroxine at the same time as receiving a proton pump inhibitor, your doctor should monitor your thyroid function and may need to adjust the dose of Thyrofix.

Make sure to respect the recommended time intervals if you need to take any of the following medications:

  • Medication used to bind bile acids and reduce high cholesterol (such as cholestyramine or colestipol):

Make sure to take Thyrofix 4-5 hours beforethese medications, as they may block the absorption of Thyrofix from the intestine.

  • Antacids (for acid indigestion), sucralfate (for stomach or intestinal ulcers), other medications containing aluminum, medications containing iron, medications containing calcium:

Make sure to take Thyrofix at least 2 hours before these medications, as they may reduce the effect of Thyrofix.

Inform your doctor or pharmacist if you are taking, have recently taken, or may need to take any of the following medications, as they may reducethe effect of this medication:

  • Propylthiouracil (thyroid medication),
  • Glucocorticoids (anti-allergic and anti-inflammatory medications),
  • Beta blockers (medications to lower blood pressure and used to treat heart diseases),
  • Sertraline (antidepressant),
  • Chloroquine or proguanil (medication to prevent or treat malaria),
  • Medications that activate certain liver enzymes, such as barbiturates (sedatives, sleeping pills), carbamazepine (antiepileptic that is also used to modify certain types of pain and to control mood disorders), products containing hypericum (a plant-based medication),
  • Medications containing estrogen used for hormone replacement during and after menopause and to prevent pregnancy,
  • Sevelamer (medication that binds to phosphate and is used to treat patients with chronic kidney failure),
  • Tyrosine kinase inhibitors (anticancer and anti-inflammatory medications, such as imatinib and sunitinib) used to treat cancer,
  • Proton pump inhibitors (medications to treat stomach ulcers and acid reflux, such as omeprazole),
  • Orlistat (medication to treat obesity).

Inform your doctor or pharmacist if you are taking, have recently taken, or may need to take any of the following medications, as they may intensifythe effect of this medication:

  • Salicylates (medications used to relieve pain and reduce fever)
  • Dicumarol (medication to prevent blood clots),
  • Furosemide in high doses of 250 mg (diuretic medication),
  • Clofibrate (medication to reduce blood fat levels),

Inform your doctor or pharmacist if you are taking, have recently taken, or may need to take any of the following medications, as they may affect the effect of this medication:

  • Ritonavir, indinavir, lopinavir (protease inhibitors, medications to treat HIV infection),
  • Phenytoin (antiepileptic).

You may need to frequently check your thyroid hormone levels. You may need to adjust your Thyrofix dose.

Inform your doctor if you are taking amiodarone (medication used to treat irregular heartbeats) as this medication may affect your thyroid gland function and activity.

If you need to undergo a diagnostic examination or procedure with iodinated contrast media, inform your doctor that you are taking this medication, as you may need to receive an injection that may affect your thyroid function.

If you are taking or have recently taken biotin, you should inform your doctor or laboratory staff when they are going to perform laboratory tests to check your thyroid hormone levels. Biotin can affect laboratory test results (see Warnings and Precautions).

Inform your doctor or pharmacist if you are taking or have recently taken any other medication, even those purchased without a prescription.

Taking Thyrofix with Food and Drinks

Inform your doctor if you consume soy products, especially if you often vary the amount you consume. Soy products may reduce the absorption of Thyrofix from the intestine and, therefore, you may need to adjust your Thyrofix dose.

Pregnancy and Breastfeeding

If you are pregnant, continue taking this medication. Talk to your doctor, as you may need to adjust your dose.

If you are taking Thyrofix with a thyroid medication to treat excessive thyroid hormone production, your doctor will recommend that you stop Thyrofix treatment when you become pregnant.

If you are breastfeeding, continue taking this medication according to your doctor's instructions. The amount of medication excreted in breast milk is so small that it will not affect the baby.

Driving and Using Machines

No studies have been conducted on the ability to drive and use machines.

This medication is not considered to have any influence on the ability to drive and use machines, as levothyroxine is identical to the natural thyroid hormone.

Thyrofix Contains Sodium

This medication contains less than 1 mmol of sodium (23 mg) per tablet, i.e., it is essentially "sodium-free".

3. How to take Thyrofix

Follow exactly the administration instructions of this medication as indicated by your doctor or pharmacist. In case of doubt, consult your doctor or pharmacist again.

Your doctor will determine the individual dose based on exams and laboratory tests. Generally, it starts with a low dose that is increased every 2 - 4 weeks, until the complete individual dose is reached. During the initial weeks of treatment, laboratory tests will be necessary to adjust the dose.

If your baby is born with hypothyroidism, your doctor may recommend starting with a higher dose, as it is essential to achieve rapid substitution. The recommended initial dose is 10 to 15 micrograms per kilogram of body weight during the first 3 months. From then on, your doctor will adjust the dose individually.

The normal dose range is shown in the following table. A lower individualized dose may be sufficient:

  • If you are an elderly patient,
  • If you have heart problems,
  • If you have severe or chronic abnormal thyroid function,
  • If you have low body weight or elevated goiter.

Use of Thyrofix

Recommended daily dose of Thyrofix

  • to treat benign goiter in patients with normal thyroid function

75 - 200 micrograms

  • to prevent the recurrence of goiter after surgery

75 - 200 micrograms

  • to replace natural thyroid hormones when the thyroid gland does not produce them in sufficient quantity
  • initial dose
  • maintenance dose

Adults

25 -50 micrograms*

100 - 200 micrograms

Children

13-50 micrograms*

100-150 micrograms per m2 of body surface

  • to stop the growth of tumors in patients with thyroid cancer

150 - 300 micrograms

  • to balance thyroid hormone levels when hormonal overproduction is treated with antithyroid medications

50 - 100 micrograms

  • to test thyroid function

100 micrograms:

200 micrograms (2 tablets) from 2 weeks before the test

150 micrograms:

From 4 weeks before the test 75 micrograms

(1 tablet of 75 micrograms) for two weeks, and from then on, 150 micrograms (1 tablet) until the test

200 micrograms:

200 micrograms (1 tablet) from 2 weeks before the test

  • The Thyrofix tablets of 112 micrograms, 125 micrograms, 137 micrograms, 150 micrograms, 175 micrograms or 200 micrograms are not suitable for the lower dose range indicated here, but your doctor may prescribe a lower concentration of Thyrofix tablets.

Administration

Thyrofix is used orally. Take a daily dose on an empty stomach in the morning (at least half an hour before breakfast), preferably with a little liquid, for example, with half a glass of water.

Infants can receive the complete daily dose of Thyrofix at least half an hour before the first meal of the day. Crush the tablet and mix it with a little water immediately before use and give it to the child with a little more water. Always prepare the mixture at the time of taking it.

Duration of treatment

The duration of treatment may vary depending on the indication for which it is used. Your doctor will inform you about the duration of treatment. Most patients need to take this medication for life.

If you take more Thyrofix than you should

If you took a dose higher than prescribed, you may experience symptoms such as palpitations, anxiety, agitation, or involuntary movements. In patients with neurological disorders such as epilepsy, convulsions may occur in isolated cases. In the case of patients at risk of psychotic disorders, symptoms of acute psychosis may occur. If this happens, consult your doctor.

If you forget to take Thyrofix

Do not take a double dose to make up for the forgotten dose, take the normal dose the next day.

If you interrupt treatment with Thyrofix

For the treatment to be effective, this medication must be taken regularly, with the dose prescribed by your doctor. Do not change, interrupt, or stop treatment without consulting your doctor. Stopping treatment definitively or temporarily could cause the symptoms to recur.

If you have any other questions about the use of this medication, ask your doctor or pharmacist.

4. Possible adverse effects

Like all medications, this medication can cause adverse effects, although not all people experience them.

You may experience one or more of the following side effects if you take more than the prescribed amount or if you do not tolerate the prescribed dose (for example, if the dose is increased rapidly):

irregular or rapid heartbeats, chest pain, headache, muscle weakness or cramps, flushing (heat and redness of the face), fever, vomiting, menstrual disorders, pseudotumor cerebri (increased cranial pressure), tremors, agitation, sleep disturbances, sweating, weight loss, and diarrhea.

If you experience any of these adverse effects, contact your doctor. He will decide if you need to interrupt treatment for a few days or reduce the daily dose until the adverse effects disappear.

You may experience allergic reactions to any of the ingredients in this medication (see section 6. 'Composition of Thyrofix'). Among the allergic reactions you may experience are rash, hives, and swelling of the face or neck (angioedema). If this happens, contact your doctor immediately.

Reporting of adverse effects

If you experience any type of adverse effect, consult your doctor or pharmacist, even if it is a possible adverse effect that does not appear in this prospectus. You can also report them directly through the Spanish Pharmacovigilance System for Human Use Medicines. Website: www.notificaRAM.es. By reporting adverse effects, you can contribute to providing more information on the safety of this medication.

5. Conservation of Thyrofix

Keep this medication out of sight and reach of children.

Do not use this medication after the expiration date that appears on the blister pack after EXP and on the box after CAD. The expiration date is the last day of the month indicated.

This medication does not require special storage conditions. Keep the blisters in their box to protect them from moisture.

Medications should not be thrown down the drain or into the trash. Deposit the containers and medications you no longer need in the SIGRE Circular white symbol with a central black cross and curved arrow indicating recycling or reuse process point of the pharmacy. If in doubt, ask your pharmacist how to dispose of the containers and medications you no longer need. This way, you will help protect the environment.

6. Package contents and additional information

Composition of Thyrofix

  • The active ingredient is levothyroxine. Each tablet contains 13 micrograms, 25 micrograms, 50 micrograms, 62 micrograms, 75 micrograms, 88 micrograms, 100 micrograms, 112 micrograms, 125 micrograms, 137 micrograms, 150 micrograms, 175 micrograms, or 200 micrograms of levothyroxine sodium.
  • The other components are powdered cellulose (E460), sodium croscarmellose (E468) (see section 2), anhydrous colloidal silica (E551), microcrystalline cellulose (E460), and magnesium stearate (E572).

Appearance of the product and package contents

The Thyrofix tablets of 13, 25, 50, 62, 75, 88, 100, 112, 125, 137, 150, 175, 200 micrograms are white, biconvex, uncoated, with a diameter of 6.5 mm and an average thickness of 3.5 mm, bearing the mark '13', '25', '50', '62', '75', '88', '100', '112', '125', '137', '150', '175', '200' on one side.

Thyrofix is available in packages of 30, 50, 60, or 100 tablets, and in blisters of 15 or 25 tablets.

Only some package sizes may be marketed.

Marketing authorization holder and manufacturer

Uni-Pharma Kleon Tsetis Pharmaceutical Laboratories S.A.

14th km National Road 1,

GR-145 64 Kifissia

Greece

This medication is authorized in the member states of the European Economic Area with the following names

Netherlands: Thyrofix 13/25/50/62/75/88/100/112/125/137/150/175/200 micrograms tablets

Denmark: Medithyrox

France: Thyrofix 13/25/50/62/75/88/100/112/125/137/150/175/200 micrograms tablets

Portugal: Thyrofix 13/25/50/62/75/88/100/112/125/137/150/175/200 micrograms tablets

Spain: Thyrofix 13/25/50/62/75/88/100/112/125/137/150/175/200 micrograms tablets

Cyprus: Thyrofix 13/25/50/62/75/88/100/112/125/137/150/175/200 micrograms tablets

Poland: Medithyrox

Finland: Medithyrox 13/25/50/62/75/88/100/112/125/137/150/175/200 micrograms tablets

Sweden: Medithyrox 13/25/50/62/75/88/100/112/125/137/150/175/200 micrograms tablets

Malta: Thyrofix 25/50/75/100/150 micrograms tablets

Date of the last revision of this prospectus:September 2024

Detailed and updated information on this medication is available on the website of the Spanish Agency for Medicines and Health Products (AEMPS) http://www.aemps.gob.es

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