Thirozol

Package Leaflet: Information for the User

Thyrozol, 5 mg, coated tablets

Thyrozol, 10 mg, coated tablets

Thyrozol, 20 mg, coated tablets

Thiamazolum

Read the package leaflet carefully before taking the medicine, as it contains important information for the patient.

• Keep this package leaflet, you may need to read it again.
• If you have any further questions, ask your doctor or pharmacist.
• This medicine has been prescribed for you only. Do not pass it on to others. It may harm them, even if their symptoms are the same as yours.
• If you experience any side effects, including those not listed in this package leaflet, tell your doctor or pharmacist. See section 4.

Contents of the Package Leaflet

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

1. What is Thyrozol and what is it used for

The medicine contains thiamazole. It inhibits the excessive production of thyroid hormones in the thyroid gland, regardless of the cause.
Thyrozol is used to treat excessive production of thyroid hormones:

• when it is necessary to take the medicine to treat the thyroid gland that produces hormones in excess, especially in the case of a small goiter (swelling in the front of the neck) or no goiter,
• when thyroid surgery is planned,
• when treatment with radioactive iodine is planned, especially in cases of very high production of thyroid hormones,
• after treatment with radioactive iodine until the full effects of the treatment are seen. Thyrozol is used to prevent excessive production of thyroid hormones before planned exposure to iodine, for example, before a test using iodine-containing contrast agents:
• when there is a slight increase in thyroid hormone production without accompanying symptoms,
• when there are certain areas in the thyroid gland that produce hormones (autonomous adenomas),
• when excessive production of thyroid hormones has occurred in the past.

2. Important information before taking Thyrozol

When not to take Thyrozol

• if you are allergic (hypersensitive) to thiamazole, substances similar to thiamazole (thionamide derivatives) or any of the other ingredients of this medicine (listed in section 6),
• if laboratory tests show a decrease in the number of certain blood cells (granulocytopenia),
• if bile flow is impaired before starting treatment with Thyrozol,
• if bone marrow damage has been reported in the past after treatment with thiamazole or carbimazole,
• if acute pancreatitis has occurred in the past after administration of thiamazole or carbimazole.

Warnings and precautions

Before starting treatment with Thyrozol, discuss it with your doctor or pharmacist.
If you have had mild allergic reactions to thiamazole in the past, such as allergic rashes
or skin itching, you should talk to your doctor, who will decide whether you can take Thyrozol.
In the case of a large goiter (swelling in the front of the neck) that makes breathing difficult,
you should talk to your doctor, as the goiter may increase during treatment with Thyrozol.
Your doctor may decide to use the medicine for a short period and with regular monitoring
during treatment.
You should consult your doctor immediately if you experience symptoms such as
fever, fatigue, weight loss, and muscle and joint pain. These may be symptoms of blood vessel inflammation (vasculitis). In this case, your doctor may stop the treatment if necessary.
These symptoms usually go away after stopping the treatment.
You should stop taking Thyrozol and consult your doctor immediately if you experience
such symptoms as inflammation of the mucous membrane of the mouth, sore throat, or fever. The cause may be a serious decrease in the number of certain blood cells (agranulocytosis). This can happen especially in the first few weeks of treatment and can lead to serious consequences.
You should consult your doctor immediately if you experience fever or abdominal pain,
as these may be symptoms of pancreatitis (acute pancreatitis). It may be necessary to stop taking Thyrozol.
Thyrozol may harm the unborn child. If you are pregnant or think you may be pregnant, or if you plan to have a child, you should consult your doctor.
In the case of very high production of thyroid hormones, it may be necessary to take very high doses of Thyrozol (over 120 mg per day). In this situation, your doctor will periodically perform blood tests, as bone marrow damage is possible. If this happens, your doctor may decide to stop the treatment and, if necessary, prescribe another medicine.
If the goiter increases or thyroid function is excessively reduced during treatment with Thyrozol, your doctor may modify the dose of Thyrozol. However, such situations can also occur in the natural course of the disease. Similarly, a certain type of eye disease (endocrine orbitopathy) may occur or worsen, which is not related to treatment with Thyrozol.
During treatment with Thyrozol, it is possible to gain weight. This is a normal reaction of the body. Thyrozol affects thyroid hormones, which control energy consumption in the body.

Thyrozol and other medicines

Iodine intake affects the action of Thyrozol. Your doctor will determine the dose of Thyrozol, taking into account iodine intake and thyroid function in individual patients.
If you are taking anticoagulant medicines (to prevent blood clotting), you should tell your doctor, as normalization of thyroid function under the influence of Thyrozol may affect the action of these medicines. The same applies to other medicines.
You should tell your doctor or pharmacist about all medicines you are taking now or have taken recently, as well as any medicines you plan to take.

Pregnancy and breastfeeding

Thyrozol may harm the unborn child.
If you are pregnant or think you may be pregnant, or if you plan to have a child, you should consult your doctor.
If you are pregnant, think you may be pregnant, or plan to have a child, you should consult your doctor immediately. It may be necessary to continue treatment with Thyrozol during pregnancy if the potential benefits outweigh the risks to the mother and fetus.
Thyrozol passes into breast milk. Your doctor will decide whether it is necessary to take Thyrozol while breastfeeding. If necessary, you can take only a small dose of up to 10 mg of thiamazole.
Your doctor will regularly monitor how the newborn's thyroid is working.

Driving and using machines

Thyrozol has no effect on the ability to drive and use machines.

Important information about some ingredients of Thyrozol

If you are intolerant to some sugars, you should tell your doctor, as Thyrozol contains lactose.
The medicine contains less than 1 mmol (23 mg) of sodium per tablet, which means the medicine is considered "sodium-free".

3. How to take Thyrozol

This medicine should always be taken exactly as directed by your doctor. If you are unsure, consult your doctor.
Recommended dose
Your doctor will determine the dose individually, depending on the severity of the disease. The following doses are usually recommended.

• Adults The initial dose is 10 mg to 40 mg of Thyrozol per day (or more in some patients) and is used until the thyroid gland starts to function properly. The maintenance dose is 5 mg to 20 mg of Thyrozol per day in combination with thyroid hormones or 2.5 mg to 10 mg of Thyrozol per day without thyroid hormones.*
• Use in children and adolescents (from 3 to 17 years) The initial dose is 0.5 mg of Thyrozol per kilogram of body weight per day. Then, your doctor will decide whether a smaller maintenance dose is sufficient and whether additional thyroid hormones are necessary.* Use in children (under 2 years) Thyrozol is not recommended for use in children under 2 years.

If there is a risk of excessive production of thyroid hormones after a diagnostic test using an iodine-containing contrast agent, your doctor may recommend taking 10 mg to 20 mg of Thyrozol per day in combination with perchlorate for about 10 days (until the iodine-containing contrast agent is eliminated from the body).*
*If small doses are needed, 5 mg tablets are available.
Patient with liver disease
If you have liver function disorders or liver disease, you should tell your doctor.
In such cases, it will be necessary to reduce the dose of Thyrozol.
Patient with kidney disease
If you have kidney function disorders or kidney disease, you should tell your doctor. In such cases, it will be necessary to reduce the dose of Thyrozol.
Duration of treatment
The duration of treatment may vary depending on the reason for taking Thyrozol.
Your doctor will explain how long you should take the medicine. The duration of treatment is usually as follows:

• treatment of excessive production of thyroid hormones (without surgery): from 6 months to 2 years,
• preoperative treatment: 3-4 weeks before surgery,
• treatment before administration of radioactive iodine: until thyroid function is normalized,
• treatment after administration of radioactive iodine: 4-6 months, until the effects of radioactive iodine therapy are seen.

Administration
Tablets should be taken in the morning, after breakfast, and washed down with a small amount of liquid, e.g., half a glass of water. The tablet can be divided into equal doses.
If you are taking several tablets a day, you can also divide them into several portions and take them at regular intervals throughout the day.

Overdose of Thyrozol

If you accidentally take a higher dose of the medicine than recommended, it should not be a problem. If you have taken a higher dose several times, you should contact your doctor as soon as possible.
You may experience intolerance to cold, fatigue, dry skin, constipation, weight gain, slow heart rate, and goiter growth. Your doctor may recommend changing the dose of Thyrozol or prescribing additional thyroid hormones to avoid goiter growth.

Missed dose of Thyrozol

Do not take a double dose to make up for a missed dose. The next day, take the usual dose.
If you have any further questions about taking this medicine, ask your doctor or pharmacist.

4. Possible side effects

Like all medicines, this medicine can cause side effects, although not everybody gets them.
During treatment with Thyrozol, the following side effects may occur, in some cases even after several months of treatment.
Very common(may affect more than 1 in 10 people)

• Skin reactions of varying severity (rash, itching, itchy blisters). In most cases, they are mild and go away during further treatment with Thyrozol.

Common(may affect up to 1 in 10 people)

• Joint pain. Uncommon(may affect up to 1 in 100 people)
• If you experience symptoms such as inflammation of the mucous membrane of the mouth, sore throat, or fever, you should contact your doctor immediately. These may be symptoms of a serious decrease in the number of certain blood cells (agranulocytosis). Rare(may affect up to 1 in 1,000 people)
• Taste disorders or loss of taste.
• Fever. Very rare(may affect up to 1 in 10,000 people)
• Decreased platelet count (thrombocytopenia), decreased count of all blood cells (pancytopenia), lymph node disease (generalized lymphadenopathy).
• Disorders of hormones that regulate blood sugar levels, manifested by decreased blood sugar levels (autoimmune insulin syndrome).
• Inflammation or irritation of nerves (neuritis, polyneuropathy).
• Salivary gland swelling.
• Liver function disorders or liver inflammation (cholestatic jaundice, toxic hepatitis). Symptoms usually go away after stopping treatment.
• Acute allergic skin reactions that can occur all over the body, including blistering skin reactions (Stevens-Johnson syndrome), hair loss, inflammatory autoimmune skin and connective tissue disease (lupus erythematosus).

Frequency not known(frequency cannot be estimated from the available data)

• Pancreatitis (acute pancreatitis).
• Blood vessel inflammation (vasculitis).

Children and adolescents

Side effects in children and adolescents are similar to those observed in adults.

Reporting side effects

If you experience any side effects, including those not listed in this package 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;
Jerozolimskie Avenue 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.
By reporting side effects, you can help provide more information on the safety of this medicine.

5. How to store Thyrozol

Keep this medicine out of the sight and reach of children.
Do not use this medicine after the expiry date stated on the carton after "EXP". The expiry date refers to the last day of that month.
Do not store above 25°C.
Medicines should 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 pack and other information

What Thyrozol contains

• The active substance is thiamazole. Each coated tablet contains 5 mg, 10 mg, or 20 mg of thiamazole.
• The other ingredients are: tablet core: colloidal silica, magnesium stearate, hypromellose, talc, maize starch, lactose monohydrate, sodium carboxymethylcellulose; coating: dimeticone 100, macrogol 400, hypromellose, titanium dioxide (E171), and iron oxide (E172).

What Thyrozol looks like and contents of the pack

Thyrozol 5 mg coated tablets are yellow, biconvex, round with a dividing line on both sides.
Thyrozol 10 mg coated tablets are gray-orange, biconvex, round with a dividing line on both sides.
Thyrozol 20 mg coated tablets are brown, biconvex, round with a dividing line on both sides.
Thyrozol 5 mg and 10 mg coated tablets are available in packs of 20, 30, 50, or 100 tablets.
Thyrozol 20 mg coated tablets are available in packs of 20, 30, or 50 tablets.
Not all pack sizes may be marketed.

Marketing authorization holder

Merck Sp. z o.o.
Jerozolimskie Avenue 142B
02-305 Warsaw, Poland
Logo of the marketing authorization holder

Manufacturer

Merck Healthcare KGaA
Frankfurter Strasse 250
64293 Darmstadt, Germany
P&G Health Austria GmbH & Co. OG
Hösslgasse 20
9800 Spittal/Drau, Austria

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

Bulgaria: Thyrozol
Czech Republic: Thyrozol
Estonia: Thyrozol
France: Thyrozol
Germany: Thyrozol
Latvia: Thyrozol
Lithuania: Thyrozol
Poland: Thyrozol
Romania: Thyrozol
Slovakia: Thyrozol

Date of last revision of the package leaflet: April 2023