Thiamazole is used to treat an overactive thyroid gland by reducing the formation of thyroid hormones.
This medicine is also used to prepare for the surgical removal of the thyroid or in addition to treatment with radioactive iodine.
Take Thiamazole exactly as directed by your doctor or according to the instructions on the label. Do not take more or less than instructed by your doctor.
Take it together with food or immediately after a meal. Swallow the tablet whole with a glass of water. Try to take it at the same time each day.
The dose of this medicine will be decided by your doctor. Your doctor will advise you on the treatment timeframe depending on the type and severity of your condition.
Thiamazole must be taken regularly for it to be effective. Continue taking this medicine even when you feel better. Do not stop taking it unless instructed by the doctor.
Take the missed dose as soon as you remember. If it is almost time for your next dose, skip the missed dose and return to your normal dosing schedule.
DO NOT double a dose under any circumstances.
If you often forget to take your medicine, let your doctor and pharmacist know.
Alert your doctor if you have a history of bone marrow damage or other severe adverse reactions due to previous treatment with Thiamazole or similar medicines such as carbimazole.
Inform your doctor if you have the following conditions:
- previous cholestasis (a condition in which the flow of bile from the liver is slowed or blocked) that is not due to overactive thyroid gland
- moderate to severe granulocytopenia (a condition characterised by a low number of a type of white blood cell called granulocytes)
- liver disease
- kidney disease
Let your doctor know if you are pregnant or breastfeeding.
Be sure to check with your doctor or pharmacist before giving Thiamazole to a child. Children may be more sensitive to the side effects.
For as long as you are taking this medicine, you may need to have regular blood tests to check your body's response to the medicine. Your doctor will advise you about how often you need to have blood tests.
If you are going to have an operation, including minor surgery and dental work, inform your doctor or dentist that you are taking this medicine.
Thiamazole may cause any of the following side effects: rash, skin pigmentation, hair loss, headache, drowsiness, dizziness with sensations of spinning, nausea, vomiting, loss of taste sensation, joint and muscle pain.
Some side effects may need immediate medical help. Alert your doctor quickly if you experience any of the following:
- yellowing of the skin or eyes, abdominal pain, dark coloured urine, tiredness, swelling in the legs and ankles
- chest pain
- shortness of breath
This medicine may cause the level of your red blood cells, white blood cells and platelets to drop.
Red blood cells carry oxygen around your body. A fall in the level of red blood cells may make you feel tired and worn out.
White blood cells help your body to fight infections. A fall in the level of your white blood cells may put you at higher risk for infections, such as coughs, colds and flu, which may lead to more serious infections. Avoid crowded places and people who are sick. Alert your doctor if you have a fever, or a cough or flu that does not go away.
Platelets help your blood to clot when there is a cut in the skin. A fall in the level of your platelets may put you at risk of bleeding more than usual. Do not take part in activities where you may fall or get injured, such as contact sports. Inform your doctor if you get any unusual bruising (large bruises or several bruises, especially if the bruises appeared on their own) or bleeding that takes a long time to stop (for example, too much bleeding when you floss or brush your teeth).
Inform your doctor if any of these side effects do not go away or are severe, or if you experience other side effects.
Inform your doctor and pharmacist if you are taking any of these medicines:
- blood-thinning medicines e.g. warfarin
- medicines for heart disease e.g. digoxin
- theophylline (asthma medicine)
- medicines for high blood pressure e.g. atenolol, metoprolol
This list does not include all medicines that may interact with Thiamazole.
Always notify your doctor and pharmacist if you are taking any other medicines, including herbal tonics, such as traditional Chinese medicines, supplements and medicines you buy without a prescription.
Store in a cool, dry place away from the reach of children.
Medicines must not be used past the expiry date.