Metizol

Patient Information Leaflet

Warning! Keep this leaflet! Information on the immediate packaging is in a foreign language.
Metizol
5 mg, tablets
Thiamazolum
Please read the following information carefully before taking this medicine, as it contains
important information for the patient.

• Keep this leaflet for future reference.
• If you have any doubts, consult your doctor or pharmacist.
• This medicine has been prescribed for a specific individual. Do not share it with others. This medicine may harm another person, even if their symptoms are identical.
• If you experience any adverse reactions, including those not listed in this leaflet, inform your doctor or pharmacist. See section 4.

Table of Contents:

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

1. What Metizol is and what it is used for

Metizol is a medicine that inhibits the production of thyroid hormones. However, it does not affect the amount of already produced hormones or their release; therefore, its effects become apparent only after several days of treatment.
Due to these properties, Metizol is used in hyperthyroidism (regardless of type), in thyroid crisis, in preparation for surgical removal of the thyroid gland, and as an adjunct in radioactive iodine therapy.

2. Important information before using Metizol

When not to use Metizol

• if the patient is allergic to thiamazole, substances structurally related to thiamazole (thiourea derivatives), or any of the other ingredients of this medicine (listed in section 6);
• if the patient has a reduced number of certain blood cells (granulocytopenia);
• if the patient has cholestatic jaundice prior to starting treatment with Metizol;
• if the patient has previously experienced bone marrow damage following treatment with thiamazole or carbimazole;
• if the patient has previously experienced pancreatitis (acute pancreatitis) after administration of thiamazole or carbimazole.

Concomitant use of thiamazole and thyroid hormones should not be used in pregnant women.
Warnings and precautions
Before starting to take Metizol, discuss this with your doctor.
If the patient has previously experienced mild allergic reactions to thiamazole, such as skin rashes or
itching, inform your doctor – the doctor will decide whether the patient can take
Metizol.
In case of a large goitre causing breathing difficulties, discuss this with
your doctor, as the goitre may enlarge during treatment with Metizol.
The doctor may decide to use the medicine for a shorter period and will regularly monitor the patient during treatment.
Before starting treatment, the doctor will order blood count tests.
Immediately consult a doctor if symptoms such as oral mucosal inflammation, sore throat, or fever occur. These symptoms may indicate a serious adverse reaction to the medicine – agranulocytosis (a marked deficiency of certain types of white blood cells responsible for immune responses in the body). These symptoms usually occur within the first weeks of treatment, but may appear even after several months of starting therapy or when restarting treatment. If such symptoms occur, the doctor will order a blood count test and may decide to discontinue treatment with Metizol.
Immediately consult a doctor if the patient develops fever or abdominal pain, as these may be symptoms of pancreatitis (acute pancreatitis).
It may be necessary to discontinue treatment with Metizol.
If very high doses of Metizol (approximately 120 mg per day) are required, the doctor will order regular blood tests, as there is a risk of bone marrow damage. If toxic effects of the medicine on the bone marrow occur, the doctor may decide to discontinue treatment and, if necessary, prescribe another medicine.
If goitre enlargement occurs during treatment with Metizol or if thyroid function becomes excessively suppressed, the doctor may modify the dose of Metizol and, if necessary, additionally prescribe thyroid hormones.
Metizol may harm the unborn child. If the patient may become pregnant, she should use a reliable method of contraception from the start of treatment and throughout therapy.
During treatment, the onset or worsening of eye disease known as endocrine ophthalmopathy may occur, which is unrelated to treatment with Metizol.
Weight gain may occur during treatment with Metizol. This is a normal bodily response. Metizol affects thyroid hormones, which regulate energy consumption in the body.
Children and adolescents
The safety and efficacy of Metizol have not been studied in children under 2 years of age.
Metizol can be used in children and adolescents aged 3 to 17 years (see section 3). For additional information, consult your doctor.
Metizol with other medicines
Inform your doctor or pharmacist about all medicines the patient is currently taking or has recently taken, as well as any medicines the patient plans to take, including those available without a prescription.
The effect of thiamazole is reduced by:

• iodine;
• medicines containing iodine (e.g. amiodarone – a medicine used to treat heart rhythm disorders);
• radiological contrast agents. Thiamazole reduces the uptake of radioactive iodine by the thyroid gland.

If anticoagulant medicines (preventing blood clotting) are being used, inform your doctor, as normalization of thyroid function due to Metizol treatment may affect the action of these medicines.
This may also apply to other medicines. As thyroid hormone levels return to normal due to treatment with Metizol, blood levels of certain concomitantly administered medicines may change. Therefore, dosage adjustment of concomitantly administered medicines may be necessary.
Metizol with food and drink
Metizol can be taken independently of meals.
Pregnancy, breastfeeding and fertility
Metizol may harm the unborn child.
If the patient may become pregnant, she should use a reliable method of contraception from the start of treatment and throughout therapy.
If the patient is pregnant, suspects she may be pregnant, or is planning to have a child, she should immediately consult her doctor.
Continuation of treatment with Metizol during pregnancy may be necessary if potential benefits outweigh the risks to the mother and fetus.
During pregnancy, concomitant use of Metizol and thyroid hormones is not permitted.
During breastfeeding, Metizol may be used only in low doses, up to 10 mg per day. However, thyroid hormones must not be taken simultaneously. The infant of a patient treated with Metizol who is breastfeeding should be regularly examined by a doctor who will monitor thyroid function in the child.
Patients receiving high doses of Metizol must not breastfeed.
Driving and operating machinery
Metizol has a minor influence on the ability to drive and operate machinery.
This medicine may cause dizziness (see section 4).
Patients experiencing this adverse effect should not drive motor vehicles or operate machinery until the effect has completely subsided.
Metizol contains monohydrate lactose
If the patient has previously been diagnosed with intolerance to certain sugars, the patient should contact the doctor before taking the medicine.

3. How to use the medicine Metizol

This medicine should always be taken as directed by the doctor. If in doubt, consult a doctor or pharmacist.

Recommended dosage
The doctor determines the dosage individually for each patient, depending on the severity of hyperthyroidism and the size of the goitre.
The initial daily dose is usually 40 mg to 60 mg (8 to 12 tablets), administered in 3 or 4 divided doses. This dosage is maintained until thyroid function is suppressed (usually 2–3 weeks, although sometimes this dosage must be maintained for up to 8 weeks or longer). Then, the dose should be gradually reduced to a maintenance dose of usually 5 mg to 20 mg (1 to 4 tablets) per day. This dose may be given as a single daily dose or in 2 divided doses.

In the treatment of thyroid storm, the medicine is initially given at a dose of 100 mg (20 tablets), followed by 30 mg (6 tablets) every 8 hours.

Treatment of hyperthyroidism with Metizol usually lasts from 6 months to 2 years.

In preparation for thyroidectomy, the medicine is usually used for 3–4 weeks prior to surgery.

Elderly patients:
Dosage adjustment is not necessary.

Use in children and adolescents (aged 3 to 17 years):
In children and adolescents aged 3 years and older, the dose is adjusted according to the patient's body weight.
Initially, a dose of 0.5 mg/kg body weight, divided into 2 or 3 equal doses, is usually used.
Later, the doctor may recommend reducing the dose. The total daily dose should not exceed 40 mg.
Use is not recommended in children under 2 years of age.

Patients with renal function impairment:
Dosage adjustment is not necessary.

Patients with hepatic function impairment:
If there are impairments in liver function or liver disease, inform the doctor. In such cases, a reduction in the dose of Metizol may be necessary.

Metizol should be taken regularly.

Use of a higher than recommended dose of Metizol
If a higher than recommended dose of Metizol is taken, consult a doctor immediately. The doctor will initiate appropriate management, including, among others, induction of vomiting, gastric lavage, administration of activated charcoal, and symptomatic treatment.

In case of overdose, symptoms may include, among others: nausea, vomiting, muscle pain, constipation, headache, menstrual disorders in women, decreased body temperature, enlargement or appearance of goitre (swelling in the front of the neck), excessive drowsiness or lethargy, fatigue, weight gain, excessive dryness of the skin, and insomnia.

Missed dose of Metizol
If a dose of Metizol is missed at the scheduled time, take it as soon as possible. However, if it is almost time for the next dose, skip the missed dose.

Do not take a double dose to make up for a missed dose.

Stopping treatment with Metizol
Premature discontinuation of treatment with Metizol may result in worsening of hyperthyroidism.

If in doubt about the use of this medicine, consult a doctor or pharmacist.

4. Possible adverse reactions

Like all medicines, this medicine can cause adverse reactions, although not everyone will experience them.
Adverse reactions may occur:
Very commonly (may affect more than 1 in 10 people)
Commonly (may affect up to 1 in 10 people)
Uncommonly (may affect fewer than 1 in 100 people)
Rarely (may affect up to 1 in 1,000 people)
Very rarely (may affect up to 1 in 10,000 people)
Frequency not known (frequency cannot be estimated from available data)
If any of the following adverse reactions occur, stop using the medicine and
contact your doctor immediately:

• Symptoms such as: inflammation of the oral mucosa, sore throat, fever, which may indicate an uncommon adverse reaction – agranulocytosis (a significant decrease in the number of certain types of white blood cells). These symptoms may appear within the first weeks of treatment or only after several weeks or months of using the medicine. In addition, the following adverse reactions may occur:

Very common adverse reactions:

• Allergic skin reactions of varying severity (itching, rash, urticaria) – usually mild and resolve during continued use of the medicine.

Common adverse reactions:

• Joint pain, which may occur even after several months of treatment.

Uncommon adverse reactions:

• Taste disturbances (altered sense of taste, loss of taste) – these symptoms may resolve after discontinuation of treatment, although this may take several weeks;
• Fever.

Rare adverse reactions:

• Thrombocytopenia (decreased platelet count; may manifest as excessive bleeding, e.g. after procedures, nosebleeds, frequent bruising, presence of blood in stool or urine, petechial hemorrhages on the skin);
• Pancytopenia (decreased number of all blood cells);
• Generalized lymphadenopathy (enlargement of lymph nodes), decreased blood glucose concentration (caused by disturbances in glucose regulation processes);
• Nerve inflammation, polyneuropathy (nerve damage, may manifest as numbness and tingling in the hands, feet, and face);
• Salivary gland swelling;
• Cholestatic jaundice (manifested by yellowing of the skin, mucous membranes, and whites of the eyes) and toxic hepatitis – these symptoms usually resolve after discontinuation of the medicine;
• Severe forms of skin allergic reactions, including generalized skin inflammation;
• Hair loss;
• Drug-induced lupus erythematosus (an immunologically mediated disease; may manifest, among others, as fatigue, loss of appetite, and the appearance of a characteristic butterfly-shaped rash on the face).

Frequency not known:

• Dizziness;
• Pancreatitis (acute inflammation of the pancreas).

Children and adolescents
The type, frequency, and severity of adverse reactions in children and adolescents are similar to those observed in adults.

Reporting of adverse reactions
If any adverse reactions occur, including any not listed in this leaflet, inform your doctor or pharmacist. Adverse reactions can be reported directly to the Department of Monitoring Adverse Reactions of Medicinal Products at 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.
Reporting adverse reactions helps to gather more information on the safety of using the medicine.

5. How to store Metizol

Keep in the original packaging.
The medicine should be stored out of sight and reach of children.
Do not use this medicine after the expiry date stated on the cardboard box.
The expiry date refers to the last day of the stated month.
Medicines must not be disposed of via wastewater or household waste. Ask your pharmacist how to dispose of medicines no longer required. This will help protect the environment.

6. Contents of the packaging and other information

What Metizol contains

• The active substance is tiamazole.
• The other ingredients are: monohydrate lactose, potato starch, povidone, talc, magnesium stearate.

What Metizol looks like and contents of the pack
Metizol is a white, round, biconvex tablet, with the imprint "M" on one side and smooth on the other side.
The pack contains 50 tablets (2 blisters of 25 tablets each).
For further detailed information, please contact the marketing authorisation holder or the parallel importer.
Marketing authorisation holder in Bulgaria, country of export:
Mylan EOOD
Office building „Serdika Offices”
Sitnyakovo Blvd., No.48, fl. 7
1505 Sofia, Bulgaria
Manufacturer:
ICN Polfa Rzeszów S.A.
Przemysłowa 2
35-959 Rzeszów, Poland
Parallel importer:
Aga Kommerz spol. s r.o.
Frydecka 2006
737 01 Český Těšín
Czech Republic
Repackaged in:
Pharma Innovations Sp. z o.o.
Jagiellońska 76
03-301 Warsaw
CEFEA Sp. z o.o. Sp. komandytowa
Działkowa 56
02-234 Warsaw
Euceryn Manufacturing Plant E.Z.M. KONSTANTY COEL S.J.
Wł. Żeleńskiego 45
31-353 Kraków
Medezin Sp. z o.o.
Zbąszyńska 3
91-342 Łódź
Marketing authorisation number in Bulgaria, country of export: 9900341
Parallel import authorisation number: 246/22