Medithirox

Leaflet accompanying the packaging: information for the user

Medithyrox, 13 micrograms, tablets

Medithyrox, 25 micrograms, tablets

Medithyrox, 50 micrograms, tablets

Medithyrox, 62 micrograms, tablets

Medithyrox, 75 micrograms, tablets

Medithyrox, 88 micrograms, tablets

Medithyrox, 100 micrograms, tablets

Medithyrox, 112 micrograms, tablets

Medithyrox, 125 micrograms, tablets

Medithyrox, 137 micrograms, tablets

Medithyrox, 150 micrograms, tablets

Medithyrox, 175 micrograms, tablets

Medithyrox, 200 micrograms, tablets

Sodium levothyroxine

You should carefully read the contents of the leaflet before taking the medicine, as it contains important information for the patient.

• You should keep this leaflet, so that you can read it again if you need to.
• If you have any doubts, you should consult your doctor or pharmacist.
• This medicine has been prescribed specifically for you. Do not pass it on to others. The medicine may harm them, even if their symptoms are the same as yours.
• If you experience any side effects, including those not listed in the leaflet, you should tell your doctor or pharmacist. See section 4.

Table of contents of the leaflet

• 1. What is Medithyrox and what is it used for
• 2. Important information before taking Medithyrox
• 3. How to take Medithyrox
• 4. Possible side effects
• 5. How to store Medithyrox
• 6. Contents of the packaging and other information

1. What is Medithyrox and what is it used for

Sodium levothyroxine, the active substance of Medithyrox, is a synthetic thyroid hormone used to treat thyroid diseases and disorders. It has the same effect as the thyroid hormones that occur naturally in the body.
Medithyrox is used:

• to treat a simple goiter (mainly in adults) with normal thyroid function,
• to prevent goiter recurrence after its surgical removal,
• as replacement therapy for natural thyroid hormones when the patient's thyroid gland does not produce enough hormones,
• to inhibit the growth of tumors in patients with thyroid cancer.

Medithyrox 13 micrograms, 25 micrograms, 50 micrograms, 62 micrograms, 75 micrograms, 88 micrograms, and 100 micrograms are also used to adjust thyroid hormone levels when excessive hormone secretion is being treated with antithyroid drugs.
Medithyrox 75 micrograms, 100 micrograms, 150 micrograms, and 200 micrograms may also be used for thyroid function testing.

2. Important information before taking Medithyrox

When not to take Medithyrox

You should not take Medithyrox with antithyroid drugs during pregnancy (see "Pregnancy and breastfeeding" below).

Warnings and precautions

Before starting Medithyrox, you should discuss it with your doctor or pharmacist if you have any of the following heart diseases:

• insufficient blood flow in the coronary arteries (angina pectoris),
• heart failure,
• rapid and irregular heartbeat,
• high blood pressure,
• fatty deposits in the arteries (arteriosclerosis).

These diseases must be under the control of your doctor before starting Medithyrox or before performing a thyroid suppression test. During Medithyrox treatment, it is necessary to frequently check thyroid hormone levels. If there is any uncertainty about whether you have any of these disorders or if they are not being treated, you should contact your doctor.
Your doctor will check if you have adrenal gland disorders, pituitary gland disorders, or uncontrolled overproduction of thyroid hormones (autonomous thyroid function), as these disorders must be under the control of your doctor before starting Medithyrox or before performing a thyroid suppression test.
You should talk to your doctor

• Do not use Medithyrox to lose weight.If your blood thyroid hormone levels are normal, taking extra thyroid hormones will not lead to weight loss. Taking extra thyroid hormones can cause serious, even life-threatening, side effects, especially when used in combination with certain weight-loss medications.
• before starting or stopping orlistat or changing orlistat treatment (a weight-loss medication), closer monitoring and dose adjustment may be necessary.

Children and adolescents
Partial hair loss may occur in children during the first few months of treatment, but this side effect is usually temporary and followed by hair regrowth.
When starting levothyroxine treatment in premature infants with very low birth weight, regular blood pressure monitoring is necessary, as a sudden drop in blood pressure (so-called circulatory collapse) may occur.
Elderly patients
Elderly patients require careful dosing and frequent check-ups.

Medithyrox and other medicines

You should tell your doctor or pharmacist about any of the following medicines you are currently taking or have recently taken, as well as any medicines you plan to take, as Medithyrox may affect their action:

• antidiabetic medicines (medicines that lower blood sugar levels): Medithyrox may weakenthe action of antidiabetic medicines, so additional blood sugar tests may be necessary, especially at the start of Medithyrox treatment. During Medithyrox treatment, it may be necessary to adjust the dose of antidiabetic medicines.
• coumarin derivatives (medicines that prevent blood clotting): Medithyrox may increasethe action of these medicines, which may increase the risk of bleeding, especially in elderly patients. Regular checks of blood clotting parameters may be necessary at the start and during Medithyrox treatment. During Medithyrox treatment, it may be necessary to adjust the dose of coumarin derivatives.
• proton pump inhibitors: Proton pump inhibitors (such as omeprazole, esomeprazole, pantoprazole, rabeprazole, and lansoprazole) are used to reduce stomach acid production, which may weaken the absorption of levothyroxine from the intestine and make it less effective. If you are taking levothyroxine while being treated with proton pump inhibitors, your doctor should monitor your thyroid function and adjust the Medithyrox dose if necessary.

You should remember to maintain the recommended time intervalsbetween taking medicines if you need to take any of the following medicines:

• bile acid-binding resins and cholesterol-lowering medicines (such as cholestyramine or colestipol). Medithyrox should be taken 4-5 hours beforethese medicines, as they may inhibit its absorption from the intestine.
• antacids (medicines used to relieve heartburn), sucralfate (used to treat stomach or intestinal ulcers), other medicines containing aluminum, iron-containing medicines, or calcium-containing medicines. Medithyrox should be taken at least 2 hours beforethese medicines, as they may reduce the action of Medithyrox.

You should tell your doctor or pharmacist about any of the following medicines you are currently taking or have recently taken, as well as any medicines you plan to take, as they may reducethe action of Medithyrox:

• propylthiouracil (an antithyroid medicine),
• glucocorticoids (anti-allergic and anti-inflammatory medicines),
• beta-adrenergic blockers (medicines that lower blood pressure and are used to treat heart diseases),
• sertraline (an antidepressant),
• chloroquine or proguanil (medicines used to treat or prevent malaria),
• medicines that stimulate certain liver enzymes, such as barbiturates (sedatives, sleeping pills), carbamazepine (an antiepileptic medicine, also used to relieve certain types of pain and control mood disorders), and herbal medicines containing St. John's Wort,
• estrogen-containing medicines used for hormone replacement therapy during menopause and postmenopause, or to prevent pregnancy,
• sevelamer (a phosphate-binding medicine used to treat patients with kidney failure),
• orlistat (a medicine used to treat obesity)
• tyrosine kinase inhibitors (e.g., imatinib and sunitinib), used to treat cancer
• tricyclic antidepressants (e.g., amitriptyline, imipramine), used to treat depression

You should tell your doctor or pharmacist about any of the following medicines you are currently taking or have recently taken, as well as any medicines you plan to take, as they may increasethe action of Medithyrox:

• salicylates (medicines used to relieve pain and reduce fever),
• dicumarol (a medicine used to prevent blood clots),
• high-dose furosemide (250 mg) (a medicine used to increase urine production),
• clofibrate (a medicine that lowers blood lipid levels).

You should tell your doctor or pharmacist about any of the following medicines you are currently taking or have recently taken, as well as any medicines you plan to take, as they may affect the action of Medithyrox:

• ritonavir, indinavir, lopinavir (protease inhibitors, medicines used to treat HIV infections),
• phenytoin (an antiepileptic medicine). Regular monitoring of thyroid hormone levels may be necessary. Dose adjustment of Medithyrox may be necessary.

You should inform your doctor if you are taking amiodarone (an antiarrhythmic medicine), as this medicine may affect thyroid function and the action of the thyroid gland.
If you need to undergo a diagnostic test or imaging study using a contrast agent containing iodine, you should inform your doctor about taking Medithyrox, as you may be given an injection that will affect thyroid function.
If you are currently taking or have recently taken biotin, you must inform your doctor or laboratory staff if you are going to have thyroid hormone laboratory tests. Biotin may affect laboratory test results (see "Warnings and precautions").
You should tell your doctor or pharmacist about any other medicines you are currently taking or have recently taken, including those available without a prescription.
Thyroid hormones should not be given to lose weight. Taking thyroid hormones will not lead to weight loss if your thyroid hormone levels are normal. Increasing the dose without special recommendation from your doctor may lead to serious or even life-threatening side effects. You should not take high doses of thyroid hormones with certain weight-loss medicines, such as amfepramone, cathyne, or phenylpropanolamine, as the risk of serious or even life-threatening side effects may increase.

Medithyrox with food and drink

You should tell your doctor if you consume soy products, especially if you change the amount of soy products you consume. Soy products may reduce the absorption of Medithyrox from the intestine, so a dose adjustment may be necessary.

Pregnancy and breastfeeding

During pregnancy, you should continue taking Medithyrox. You should talk to your doctor, as a dose adjustment may be necessary.
If you are taking Medithyrox with an antithyroid medicine to treat overproduction of thyroid hormones, your doctor will advise you to stop taking Medithyrox after becoming pregnant.
During breastfeeding, you should continue taking Medithyrox as recommended by your doctor. The amount of medicine that passes into breast milk is so small that it will not affect the baby.

Driving and using machines

No studies have been conducted on the effect of Medithyrox on the ability to drive and use machines.
Since levothyroxine is the same as the thyroid hormone that occurs naturally in the body, it is not expected that Medithyrox will have any effect on the ability to drive and use machines.

Medithyrox contains sodium

This medicine contains less than 1 mmol (23 mg) of sodium per tablet, which means it is considered "sodium-free".

3. How to take Medithyrox

Medithyrox should always be taken as directed by your doctor or pharmacist. If you have any doubts, you should consult your doctor or pharmacist.
Your doctor will determine your individual dose of Medithyrox based on tests and laboratory results. Treatment usually starts with a small dose, which is gradually increased every 2-4 weeks until the full individual dose is reached. During the first few weeks of treatment, you will need to have laboratory tests to adjust the dose.
If a child is born with hypothyroidism, your doctor may recommend starting treatment with a higher dose, as rapid replacement therapy is important. The recommended initial dose is 10-15 micrograms per kilogram of body weight for the first 3 months. Then, your doctor will adjust the dose individually.
The following table shows the usual dose ranges. A smaller individual dose may be sufficient,

• to inhibit the growth of tumors in patients with thyroid cancer
• 150-300 micrograms
• to adjust thyroid hormone levels when excessive hormone secretion is being treated with antithyroid drugs
• 50-100 micrograms
• for thyroid function testing Medithyrox, 100 micrograms: 200 micrograms (2 tablets) - start taking 2 weeks before the test

Medithyrox, 150 micrograms:
Start 4 weeks before the test - 75 micrograms (1 tablet of 75 micrograms) for two weeks, and then 150 micrograms (1 tablet of 150 micrograms) until the test
Medithyrox, 200 micrograms:
200 micrograms (1 tablet) - start taking 2 weeks before the test

• as replacement therapy for natural thyroid hormones in adults when the patient's thyroid gland does not produce enough hormones adults

initial dose 25-50 micrograms
maintenance dose

• 100-200 micrograms
• as replacement therapy for natural thyroid hormones in children when the patient's thyroid gland does not produce enough hormones

children
initial dose 12.5-50 micrograms

• 100-150 micrograms per square meter of body surface area

maintenance dose

Newborns, infants, and children

initial dose in congenital

• 10-15 micrograms per kilogram of body weight

hypothyroidism
initial dose in acquired
12.5-50 micrograms
hypothyroidism
maintenance dose 100-150 micrograms per square meter of body surface area
Medithyrox tablets of 112 micrograms, 125 micrograms, 137 micrograms, 150 micrograms, 175 micrograms, or 200 micrograms are not suitable for administering the smaller doses mentioned here, but your doctor may prescribe Medithyrox tablets of lower strength.
Administration
Medithyrox should be taken orally. You should take a single daily dose of the medicine in the morning, on an empty stomach (at least half an hour before breakfast), preferably with a small amount of liquid (e.g., half a glass of water).
Infants may receive their entire daily dose of Medithyrox at least 30 minutes before their first meal of the day. Immediately before administration, the tablet should be crushed and mixed with a small amount of water, and the resulting suspension should be given to the child with a small amount of liquid. The suspension should be prepared fresh each time.
Duration of treatment
The duration of treatment may vary depending on the disease for which Medithyrox is being used. Therefore, your doctor will inform you how long you should take the medicine. Most patients take Medithyrox for the rest of their lives.

Taking a higher dose of Medithyrox than recommended

If you take a higher dose than recommended, you may experience symptoms such as rapid heartbeat, anxiety, agitation, or involuntary movements. In patients with neurological disorders, such as epilepsy, seizures may occur in rare cases. In patients at risk of psychotic disorders, symptoms of acute psychosis may occur. If any of these situations occur, you should contact your doctor.

Missing a dose of Medithyrox

You should not take a double dose to make up for a missed tablet, but take the normal dose the next day.

Stopping Medithyrox treatment

To ensure that Medithyrox treatment is effective, you should take it regularly in the dose prescribed by your doctor. Without consulting your doctor, you should not change, stop, or discontinue treatment.
Stopping or temporarily discontinuing Medithyrox may cause the symptoms to recur in the patient.
If you have any further doubts about taking this medicine, you should consult your doctor or pharmacist.

4. Possible side effects

Like all medicines, Medithyrox can cause side effects, although not everybody gets them.
You should not expect side effectsif you take Medithyrox in the dose prescribed by your doctor and have regular laboratory tests.
This is because levothyroxine, the active substance of Medithyrox, is the same as the thyroid hormone that occurs naturally in the body.
In the case of taking a higher dose of Medithyrox than prescribed or intolerance to the recommended dose (e.g., rapid increase in levothyroxine dose), one or more of the following side effects may occur:
weight loss, increased appetite, tremors, anxiety, agitation, restlessness, insomnia, headache, increased intracranial pressure with eye swelling (especially in children), heart failure, heart attack, palpitations, arrhythmias, especially accelerated heart rate, chest pain with a feeling of constriction (angina pectoris), increased blood pressure, vomiting, diarrhea, nausea, cramps, shortness of breath, muscle weakness and cramps, irregular menstrual periods, excessive sweating, hair loss, feeling of heat (flushing), fever.
If you experience any of these side effects, you should contact your doctor. Your doctor will decide whether to stop treatment for a few days or reduce the dose until the side effects disappear.
Allergic reactions to any of the ingredients of Medithyrox (see section 6) are possible. Allergic reactions may include swelling of the face or throat (angioedema). If you experience such symptoms, you should contact your doctor immediately.

Reporting side effects

If you experience any side effects, including those not listed in the leaflet, you should tell your doctor or pharmacist. Side effects can be reported directly to the Department of Drug Safety Monitoring of the Office for Registration of Medicinal Products, Medical Devices, and Biocidal Products, Al. Jerozolimskie 181C, 02-222 Warsaw, Tel.: +48 22 49 21 301, Fax: +48 22 49 21 309, website: https://smz.ezdrowie.gov.pl
Side effects can also be reported to the marketing authorization holder.
Reporting side effects will help to gather more information on the safety of the medicine.

5. How to store Medithyrox

The medicine should be stored out of the sight and reach of children.
Do not use Medithyrox after the expiration date stated on the blister and carton after EXP. The expiration date refers to the last day of the month.
There are no special storage instructions for the medicinal product. Store in the original packaging to protect from moisture.
Medicines should not be disposed of via wastewater or household waste. You should ask your pharmacist how to dispose of medicines that are no longer needed. This will help protect the environment.

6. Contents of the packaging and other information

What Medithyrox contains

• The active substance of Medithyrox 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 ingredients are: cellulose, powder (E460), croscarmellose sodium (E468) (see section 2), colloidal anhydrous silica (E551), microcrystalline cellulose (E460), and magnesium stearate (E572).

What Medithyrox looks like and contents of the packaging

Medithyrox 13 micrograms tablets are white, round, biconvex, uncoated tablets with a diameter of 6.5 mm and an average thickness of 3.5 mm, with the number "13" engraved on one side.
Medithyrox 25 micrograms tablets are white, round, biconvex, uncoated tablets with a diameter of 6.5 mm and an average thickness of 3.5 mm, with the number "25" engraved on one side.
Medithyrox 50 micrograms tablets are white, round, biconvex, uncoated tablets with a diameter of 6.5 mm and an average thickness of 3.5 mm, with the number "50" engraved on one side.
Medithyrox 62 micrograms tablets are white, round, biconvex, uncoated tablets with a diameter of 6.5 mm and an average thickness of 3.5 mm, with the number "62" engraved on one side.
Medithyrox 75 micrograms tablets are white, round, biconvex, uncoated tablets with a diameter of 6.5 mm and an average thickness of 3.5 mm, with the number "75" engraved on one side.
Medithyrox 88 micrograms tablets are white, round, biconvex, uncoated tablets with a diameter of 6.5 mm and an average thickness of 3.5 mm, with the number "88" engraved on one side.
Medithyrox 100 micrograms tablets are white, round, biconvex, uncoated tablets with a diameter of 6.5 mm and an average thickness of 3.5 mm, with the number "100" engraved on one side.
Medithyrox 112 micrograms tablets are white, round, biconvex, uncoated tablets with a diameter of 6.5 mm and an average thickness of 3.5 mm, with the number "112" engraved on one side.
Medithyrox 125 micrograms tablets are white, round, biconvex, uncoated tablets with a diameter of 6.5 mm and an average thickness of 3.5 mm, with the number "125" engraved on one side.
Medithyrox 137 micrograms tablets are white, round, biconvex, uncoated tablets with a diameter of 6.5 mm and an average thickness of 3.5 mm, with the number "137" engraved on one side.
Medithyrox 150 micrograms tablets are white, round, biconvex, uncoated tablets with a diameter of 6.5 mm and an average thickness of 3.5 mm, with the number "150" engraved on one side.
Medithyrox 175 micrograms tablets are white, round, biconvex, uncoated tablets with a diameter of 6.5 mm and an average thickness of 3.5 mm, with the number "175" engraved on one side.
Medithyrox 200 micrograms tablets are white, round, biconvex, uncoated tablets with a diameter of 6.5 mm and an average thickness of 3.5 mm, with the number "200" engraved on one side.
Medithyrox is packaged in blisters.
The packaging contains 30, 50, 60, or 100 tablets in several blisters of 15 or 25 tablets, in a cardboard box.
Not all pack 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
emergency@uni-pharma.gr

This medicine is authorized in the Member States of the European Economic Area under the following names:

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

Date of last revision of the leaflet

February 23, 2023