Metizol

Package Leaflet: Information for the Patient

Warning! The leaflet should be kept. Information on the immediate packaging in a foreign language.

Metizol, 5 mg, Tablets

Thiamazolum

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

• The leaflet should be kept so that it can be read again if necessary.
• In case of any doubts, the patient should consult a doctor or pharmacist.
• This medicine has been prescribed for a specific person. It should not be given to others. The medicine may harm another person, even if the symptoms of their disease are the same.
• If the patient experiences any side effects, including any side effects not listed in this leaflet, they should inform their doctor, pharmacist, or nurse. See section 4.

Table of Contents of the Leaflet:

• 1. What is Metizol and what is it used for
• 2. Important information before taking Metizol
• 3. How to take Metizol
• 4. Possible side effects
• 5. How to store Metizol
• 6. Package contents and other information

1. What is Metizol and what is it used for

Metizol is a medicine that inhibits the production of thyroid hormones. However, it does not affect the amount of hormones already produced or their release, so the effects of its action appear only after a few days of use.
Thanks to its properties, Metizol is used in hyperthyroidism (regardless of its type), in thyroid crisis, in preparation for thyroidectomy, and as a supportive agent in the treatment with radioactive iodine.

2. Important information before taking Metizol

When not to take Metizol

• if the patient is allergic to thiamazole, substances with a similar structure to thiamazole (thionamide derivatives) or any of the other ingredients of this medicine (listed in section 6);
• if the patient has been diagnosed with a decrease in the number of certain blood cells (granulocytopenia);
• if the patient has been diagnosed with bile stasis before starting treatment with Metizol;
• if the patient has a history of bone marrow damage after treatment with thiamazole or carbimazole;
• if the patient has a history of pancreatitis (acute pancreatitis) after administration of thiamazole or carbimazole.

Thiamazole should not be used simultaneously with thyroid hormones in pregnant women.

Warnings and precautions

Before starting to take Metizol, the patient should discuss it with their doctor.
If the patient has a history of mild allergic reactions to thiamazole, such as allergic rashes or skin itching, they should inform their doctor – the doctor will decide whether the patient can take Metizol.
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In the case of a large goiter that makes breathing difficult, the patient should discuss it with their doctor, as the goiter may increase during treatment with Metizol. The doctor may decide to use the medicine for a shorter period and regularly monitor the patient during treatment.
Before starting treatment, the doctor will order blood morphology tests.
The patient should immediately consult a doctor if they experience symptoms such as oral mucosa inflammation, sore throat, or fever. These symptoms may indicate a serious side effect of the medicine - agranulocytosis (a significant decrease in the number of certain types of white blood cells responsible for immune responses in the body). They usually occur within the first few weeks of treatment, but may also appear after several months of therapy or during the restart of treatment. If such symptoms occur, the doctor will order a blood morphology test and may decide to stop using Metizol.
The patient should immediately consult a doctor if they experience fever or abdominal pain, as these may be symptoms of pancreatitis (acute pancreatitis). It may be necessary to stop using Metizol.
In the case of the need to use very high doses of Metizol (about 120 mg per day), the doctor will order control blood tests, as bone marrow damage is possible. If toxic effects of the medicine on the bone marrow occur, the doctor may decide to interrupt treatment and, if necessary, prescribe another medicine.
If the patient experiences an increase in goiter or excessive weakening of thyroid function during treatment with Metizol, the doctor may modify the dose of Metizol and, if necessary, also order the use of thyroid hormones.
Metizol may harm the unborn child. If the patient may become pregnant, they should use a reliable method of contraception from the start of treatment and during therapy.
During treatment, the patient may also experience the occurrence or exacerbation of a eye disease called endocrine orbitopathy, which is not related to treatment with Metizol.
During treatment with Metizol, it is possible to increase body weight. This is a normal reaction of the body. Metizol affects thyroid hormones, which control energy consumption in the body.

Children and adolescents

The safety and efficacy of Metizol in children under 2 years of age have not been studied.
Metizol can be used in children and adolescents from 3 to 17 years old (see section 3). For additional information, the patient should consult a doctor.

Metizol and other medicines

The patient should tell their doctor or pharmacist about all medicines they are currently taking or have recently taken, as well as medicines they plan 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 the patient is taking anticoagulant medicines (preventing blood clotting), they should inform their doctor, as the normalization of thyroid function under the influence of Metizol may affect the action of these medicines. This may also apply to other medicines. As the thyroid hormone levels in the blood return to normal under the influence of Metizol, the levels of some concurrently used medicines may change. Therefore, a change in the dosage of the concurrently used medicines may be necessary.

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The patient should tell their doctor or pharmacist about all medicines they are currently taking or have recently taken, as well as medicines they plan to take, including those available without a prescription.

Metizol with food and drink

Metizol can be taken regardless of meals.

Pregnancy, breastfeeding, and fertility

Metizol may harm the unborn child.
If the patient may become pregnant, they should use a reliable method of contraception from the start of treatment and during therapy.
If the patient is pregnant, suspects they may be pregnant, or plans to have a child, they should immediately consult a doctor.
It may be necessary to continue treatment with Metizol during pregnancy if the potential benefits outweigh the risks to the mother and fetus.
During pregnancy, the patient should not take Metizol and thyroid hormones at the same time.
During breastfeeding, Metizol can be used in small doses, up to 10 mg per day. However, the patient should not take thyroid hormones at the same time. The child of a patient treated with Metizol who is breastfeeding should be regularly examined by a doctor who will monitor the child's thyroid function.
Patients who take high doses of Metizol should not breastfeed.

Driving and using machines

Metizol has a minor effect on the ability to drive and use machines.
The medicine may cause dizziness (see section 4). Patients who experience this side effect should not drive vehicles or operate machines until it has completely resolved.

Metizol contains lactose monohydrate

If the patient has been diagnosed with intolerance to some sugars, they should consult their doctor before taking the medicine.

3. How to take Metizol

This medicine should always be taken according to the doctor's instructions. In case of doubts, the patient should consult a doctor or pharmacist.
Recommended dose
The doctor determines the dosage individually for each patient, depending on the severity of hyperthyroidism and the size of the goiter.
The initial daily dose is usually 40 mg to 60 mg (8 to 12 tablets) and is given in 3 or 4 divided doses. This dosage is maintained until the thyroid function is inhibited (usually 2-3 weeks, although sometimes it is necessary to maintain this dosage for 8 weeks or even longer). Then, the doses of the medicine should be gradually reduced to a maintenance dose, usually 5 mg to 20 mg (1 to 4 tablets) per day. This dose is given in a single daily dose or in 2 divided doses.
In the treatment of thyroid crisis, the medicine is given initially in a dose of 100 mg (20 tablets), and then every 8 hours in a dose of 30 mg (6 tablets).
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 before the surgery.
Elderly patients:
There is no need to change the dosage.
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Use in children and adolescents (from 3 to 17 years old)
In children and adolescents over 3 years old, the dose is adjusted according to the patient's body weight.
Usually, at the beginning of treatment, 0.5 mg/kg of body weight is used, divided into 2 or 3 equal doses.
Later, the doctor may recommend reducing the dose. The total daily dose should not exceed 40 mg.
It is not recommended to use Metizol in children under 2 years old.
Patients with renal impairment:
There is no need to change the dosage.
Patients with hepatic impairment:
If the patient has liver dysfunction or liver disease, they should inform their doctor.
In such cases, it may be necessary to reduce the dose of Metizol.
Metizol should be taken regularly.

Using a higher dose of Metizol than recommended

In case of using a higher dose of Metizol than recommended, the patient should consult a doctor, who will implement appropriate procedures, including inducing vomiting, gastric lavage, and administration of activated charcoal, as well as symptomatic treatment.
In case of overdose, the following symptoms may occur: nausea, vomiting, muscle pain, constipation, headache, menstrual disorders in women, decreased body temperature, goiter or its appearance (swelling in the front of the neck), excessive drowsiness or lethargy, and fatigue, weight gain, excessive dryness of the skin, and insomnia.

Missing a dose of Metizol

If the patient misses a dose of Metizol at the scheduled time, they should take it as soon as possible. However, if the time for the next dose is approaching, the missed dose should be skipped.
The patient should not take a double dose to make up for the missed dose.

Stopping treatment with Metizol

In case of premature termination of treatment with Metizol, the patient may experience an exacerbation of hyperthyroidism.
In case of doubts related to the use of the medicine, the patient should consult a doctor or pharmacist.

4. Possible side effects

Like all medicines, Metizol can cause side effects, although not everybody gets them.
Side effects may occur:
Very common (may occur in more than 1 in 10 people)
Common (may occur in up to 1 in 10 people)
Uncommon (may occur in up to 1 in 100 people)
Rare (may occur in up to 1 in 1,000 people)
Very rare (may occur in up to 1 in 10,000 people)
Frequency not known (frequency cannot be estimated from the available data)

If one of the following side effects occurs, the patient should stop taking the medicine and immediately consult a doctor:

• Symptoms such as oral mucosa inflammation, sore throat, or fever, which may indicate an uncommon side effect - agranulocytosis (a significant decrease in the number of certain types of white blood cells).

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These symptoms may appear within the first few weeks of treatment or after several weeks or months of using the medicine.
Additionally, the following side effects may occur:

Very common side effects:

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

Common side effects:

• Joint pain, which may appear even after several months of therapy with Metizol;

Rare side effects:

• Taste disorders (altered taste, loss of taste) - these symptoms may resolve after the end of treatment, although it may take several weeks;
• Fever.

Very rare side effects:

• Thrombocytopenia (decrease in platelet count; may manifest as excessive bleeding, e.g., after procedures, nosebleeds; frequent bruising; presence of blood in stool or urine; pinpoint bleeding on the skin);
• Pancytopenia (decrease in the number of all blood cells);
• Generalized lymphadenopathy (enlargement of lymph nodes), decreased glucose levels in the blood (caused by disorders of glucose regulation in the blood);
• Nerve inflammation, polyneuropathy (nerve damage, may manifest as numbness and tingling in the hands, feet, and face);
• Salivary gland swelling;
• Cholestatic jaundice (manifesting as yellowing of the skin, mucous membranes, and eye whites) and toxic hepatitis - these symptoms usually resolve after the end of treatment with the medicine;
• Severe forms of allergic skin reactions, including generalized skin inflammation;
• Hair loss;
• Drug-induced lupus erythematosus (an immune-related disease; may manifest as fatigue, loss of appetite, and a characteristic butterfly-shaped rash on the face) .

Frequency not known:

• Dizziness;
• Pancreatitis (acute pancreatitis).

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

Reporting side effects

If the patient experiences any side effects, including any side effects not listed in this leaflet, they should inform their doctor, pharmacist, or nurse. Side effects can be reported directly to the Department of Monitoring of Adverse Reactions to Medicinal Products of the Office for Registration of Medicinal Products, Medical Devices, and Biocidal Products
Aleje Jerozolimskie 181C
02-222 Warsaw
Phone: +48 22 49 21 301
Fax: +48 22 49 21 309
Website: https://smz.ezdrowie.gov.pl.
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By reporting side effects, it is possible to gather more information on the safety of the medicine.

5. How to store Metizol

Store in the original packaging.
The medicine should be stored in a place invisible and inaccessible to children.
Do not use this medicine after the expiry date stated on the packaging. The expiry date refers to the last day of the specified month.
Medicines should not be disposed of via wastewater or household waste containers. The patient should ask their pharmacist how to dispose of medicines that are no longer used. This will help protect the environment.

6. Package contents and other information

What Metizol contains

• The active substance of the medicine is thiamazole. Each tablet contains 5 mg of thiamazole.
• The other ingredients of the medicine are: lactose monohydrate, potato starch, povidone, talc, magnesium stearate.

What Metizol looks like and what the package contains

Metizol is a white, round, flat tablet with a marking "M" on one side and a smooth surface on the other.
The package contains 50 tablets (2 blisters of 25 tablets).
For more detailed information, the patient should consult the marketing authorization holder or parallel importer.

Marketing authorization holder in Bulgaria, the country of export:

Mylan EOOD, Office building "Serdika Offices", Sitnyakovo Blvd., No.48, fl. 7, 1505 Sofia, Bulgaria

Manufacturer:

ICN Polfa Rzeszów S.A., ul. Przemysłowa 2, 35-959 Rzeszów

Parallel importer:

Delfarma Sp. z o.o., ul. Św. Teresy od Dzieciątka Jezus 111, 91-222 Łódź

Repackaged by:

Delfarma Sp. z o.o., ul. Św. Teresy od Dzieciątka Jezus 111, 91-222 Łódź
Bulgarian marketing authorization number: 9900341

Parallel import authorization number: 100/22 Date of approval of the leaflet: 23.02.2022

[Information about the trademark]
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