Full Prescribing Info
Each tablet of Thiamazole (Strumazol) 10mg contains: Thiamazole, EP 10 mg.
Each tablet of Thiamazole (Strumazol) 30mg contains: Thiamazole, EP 30 mg.
Pharmacology: Pharmacodynamics: Thiamazole (Strumazol) reduces synthesis of the thyroid hormones by inhibiting the incorporation of iodide in thyroglobulins of the thyroid gland.
Pharmacokinetics: Thiamazole (Strumazol), is well absorbed. Maximum plasma concentrations are reached 1-2 hrs after oral administration. After taking Thiamazole (Strumazol) 30 mg, a peak value of approximately 0.5 mcg/mL is obtained. The plasma half-life is 2-6 hrs and this is unchanged in hyperthyroidism.
Thiamazole (Strumazol) is concentrated in the thyroid gland immediately after absorption. The maximum concentration in the thyroid gland is reached after 1 hour. The concentration in the thyroid gland varies, depending on the dose and the time after administration, from 1 to 10 mmol. The half-life in the thyroid gland is more prolonged and important than the plasma half-life. After 20 hours, the concentration in the thyroid gland is still almost the same as that after 6 hours. The incorporation of iodide is inhibited for 24 hours by taking 10-30 mg Thiamazole (Strumazol). This means that Thiamazole (Strumazol) can usually be given once a day.
Hyperthyroidism (mild to severe); Treatment of Graves' disease; Preparation of hyperthyroid patients for thyroidectomy; Use as an adjunct to radioactive iodine therapy.
Dosage/Direction for Use
Initial dose of 15-60 mg daily. It is usually given in three divided doses but single daily dose is also possible. Improvement is usually seen in 1 to 3 weeks and control of symptoms is 1 to 2 months.
Euthyroid patient: Dose is gradually reduced to a maintenance dose, usually 5-15 mg daily. Alternatively, the dose may be continued at the initial level with supplemental levothyroxine as a blocking-replacement regimen either form of maintenance treatment usually continued for 1 to 2 years.
Children: Initial dose is 400 mcg/kg in divided doses; for maintenance this dose may be halved.
Overdose leads to hypothyroidism with associated symptoms of reduced metabolism and, due to the feedback effect, activation of the anterior pituitary with subsequent goiter growth. This can be avoided by reducing the dose, as soon as euthyroid metabolic status is reached and, where necessary, by adjuvant administration of levothyroxine.
There are no known negative sequelae from accidental ingestion of high thiamazole doses.
Thiamazole (Strumazol) must not be used in patients with: Hypersensitivity to thiamazole, to other thionamide derivatives.
Moderate to severe blood dyscrasia (granulocytopenia).
An existing cholestatic disease not caused by hyperthyroidism.
Bone marrow damage during previous treatment with thiamazole or carbimazole.
Patients with a prior history of acute pancreatitis after administration of thiamazole or carbimazole.
Combination therapy with thiamazole and thyroid hormones is contraindicated during pregnancy.
Special Precautions
At the beginning of the treatment, the patient must be clearly informed of the possible side effects (see Side Effects).
Use in pregnancy: Women of childbearing potential have to use effective contraception during treatment.
Use In Pregnancy & Lactation
From observations in man, it has become apparent that Thiamazole (Strumazol) can be harmful to the fetus. In particular, there have been a number of reports of the appearance of aplasia cutis of the skull. The evidence of the teratogenicity is as yet too weak to contraindicate use during pregnancy. Thiamazole (Strumazol) should only be used in pregnancy in consultation with a specialist. In prescribing anti-thyroids, it must be borne in mind that all thyroid depressants cross the placenta and therefore can lead to hypothyroidism and goiter formation in the fetus. In Graves' disease one must also be prepared for the onset of hyperthyroidism in the fetus and thus, it would be advisable to treat the patient on anti-thyroid.
Women of Childbearing Potential and Pregnancy: Women of childbearing potential have to use effective contraception during treatment.
Use in lactation: The use of the standard dose of (Strumazol) leads to significant quantities of thiamazole in the mother's milk. Propylthiouracil is then preferable (Strumazol) should only be used during lactation in consultation with a specialist.
Side Effects
Of course, Thiamazole (Strumazol) can lead to primary hypothyroidism if used as monotherapy. Following a reduction in thyroid function, Thiamazole (Strumazol) can also lead to thyroid gland l enlargement, with mechanical symptoms as a possible ultimate complication.
The evaluation of adverse reactions is based on the following definitions of frequency: Very common: ≥1/10; Common: ≥1/100 to <1/10; Uncommon: ≥1/1,000 to <1/100; Rare: ≥1/10,000 to <1/1,000; Very rare: <1/10,000; Not known: cannot be estimated from the available data.
Blood and lymphatic system disorders: Uncommon: agranulocytosis1.
Very rare: thrombocytopenia, pancytopenia, generalised lymphadenopathy.
Not known: aplastic anaemia.
Endocrine disorders: Very rare: insulin autoimmune syndrome (with a sharp drop in blood glucose).
Nervous system disorders: Rare: disturbances in the senses of taste (dysgeusia, ageusia)2.
Very rare: neuritis, polyneuropathy.
Gastrointestinal disorders: Very rare: acute salivary gland swelling.
Not known: acute pancreatitis.
Hepatobiliary disorders: Very rare: individual cases of cholestatic jaundice or toxic hepatitis3.
Skin and subcutaneous tissue disorders: Very common: allergic skin reactions of varying degrees (pruritus, rash, urticaria)4.
Very rare: severe forms of allergic skin reactions including generalised dermatitis, Stevens Johnson syndrome, alopecia, drug-induced lupus erythematosus.
Musculoskeletal and connective tissue disorders: Common: arthralgia5.
Not known: arthritis.
Renal and urinary disorders: Not known: nephrotic syndrome.
General disorders and administration site conditions: Rare: drug fever.
1Agranulocytosis occurs in 0.3 to 0.6% of cases. This may also become evident several weeks or months after initiation or resumption of therapy. If it occurs, this medicinal product must be discontinued. Most cases improve spontaneously.
2These may improve upon discontinuation of therapy. However, it may take several weeks for the situation to normalise.
3Symptoms general improve upon discontinuationof the medicine. Clinically unremarkable signs of cholestasis during treatment must be differentiated from disorders due to hyperthyroidism, such as elevation of GGT (gamma-glutamyltransferase) and alkaline phosphatase or its bone-specific isoenzyme.
4These usually have a mild course and often improve with continued therapy.
5This may develop gradually and occur even after several months of therapy.
Pediatric Population: Frequency, type and severity of the adverse reactions in children appear to be similar to those in adults. Severe allergic skin reactions, including Stevens-Johnson syndrome, have been reported in both adult and paediatric patients (very rare, including isolated reports: severe forms, including generalised dermatitis, have only been described in isolated cases).
Drug Interactions
Iodine deficiency increases the thyroid response to thiamazole, but an excess of iodine reduces the response. There are no known other direct interactions with other medicinal products. However, it must be taken into account that the metabolism and elimination of other medicinal products can be accelerated in hyperthyroidism. This normalises in correlation with increasing normalisation of thyroid function. The dosage must be adjusted where necessary.
In addition, there are indications that correction of hyperthyroidism may normalise the enhanced activity of anticoagulants in patients with hyperthyroidism.
Paediatric population: No interaction studies have been performed in paediatric patients.
As Thiamazole (Strumazol) leads to a change in the metabolism, it may be necessary to adjust dosage of other drugs.
Store protected from light and moisture at temperatures not exceeding 30°C.
MIMS Class
Antithyroid Agents
ATC Classification
H03BB02 - thiamazole ; Belongs to the class of sulfur-containing imidazole derivative agents. Used in the management of thyroid diseases.
Strumazol tab 10 mg
100's (P1,764.22/pack)
Strumazol tab 30 mg
30's (P1,609.62/pack)
Register or sign in to continue
Asia's one-stop resource for medical news, clinical reference and education
Already a member? Sign in
Register or sign in to continue
Asia's one-stop resource for medical news, clinical reference and education
Already a member? Sign in