Drug Action
Thyrotropin alfa is a recombinant form of thyrotrophin (thyroid stimulating hormone).
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Drug reference
Thyrotropin alfa is a recombinant form of thyrotrophin (thyroid stimulating hormone).
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Detection of thyroid remnants and thyroid cancer in post- thyroidectomy patients, together with serum thyroglobulin testing (with or without radioiodine imaging) | To increase radio-iodine uptake for the ablation of thyroid remnant tissue in suitable post- thyroidectomy patients ▶BY INTRAMUSCULAR INJECTION ▶Adult: 900 micrograms every 24 hours for 2 doses, dose to be administered into the gluteal muscle, consult product literature for further information on indications and dose
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Presence of thyroglobulin autoantibodies may give false negative results
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Contra-indicated if previous hypersensitivity to bovine or human thyrotrophin.
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▶Common or very common Asthenia. dizziness. headache. nausea. vomiting ▶Uncommon Chills. diarrhoea. feeling hot. fever. flushing. hypersensitivity. influenza. influenza like illness. pain. paraesthesia. pulmonary reaction. skin reactions. taste altered ▶Rare or very rare Atrial fibrillation. hyperthyroidism ▶Frequency not known Arthralgia. dyspnoea. goitre. hyperhidrosis. myalgia. neoplasm complications. palpitations. residual metastases enlarged. stroke. tremor
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Avoid.
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Avoid.
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There can be variation in the licensing of different medicines containing the same drug. Powder for solution for injection ▶Thyrogen (Genzyme Therapeutics Ltd) Thyrotropin alfa 900 microgram Thyrogen 900microgram powder for solution for injection vials | 2 vial P £583.04 9.1 Hyperthyroidism Antithyroid drugs Overview Antithyroid drugs are used for hyperthyroidism either to prepare patients for thyroidectomy or for long-term Endocrine system management. In the UK carbimazole below is the most commonly used drug. Propylthiouracil p. 815 should be reserved for patients who are intolerant of carbimazole or for those who experience sensitivity reactions to carbimazole (sensitivity is not necessarily displayed to both drugs), and for whom other treatments are inappropriate. Both drugs act primarily by interfering with the synthesis of thyroid hormones. Over-treatment with antithyroid drugs can result in the rapid development of hypothyroidism and should be avoided particularly during pregnancy because it can cause fetal goitre. A combination of carbimazole with levothyroxine sodium p. 816 daily, may be used in a blocking-replacement regimen; therapy is usually given for 18 months. The blocking- replacement regimen is not suitable during pregnancy. Iodine has been used as an adjunct to antithyroid drugs for 10 to 14 days before partial thyroidectomy; however, there is little evidence of a beneficial effect. Iodine should not be used for long-term treatment because its antithyroid action tends to diminish. Radioactive sodium iodide (131 I) solution is used increasingly for the treatment of thyrotoxicosis at all ages, particularly where medical therapy or compliance is a problem, in patients with cardiac disease, and in patients who relapse after thyroidectomy. Propranolol hydrochloride p. 162 is useful for rapid relief of thyrotoxic symptoms and may be used in conjunction with antithyroid drugs or as an adjunct to radioactive iodine. Beta-blockers are also useful in neonatal thyrotoxicosis and in supraventricular arrhythmias due to hyperthyroidism. Propranolol hydrochloride has been used in conjunction with iodine to prepare mildly thyrotoxic patients for surgery but it is preferable to make the patient euthyroid with carbimazole. Laboratory tests of thyroid function are not altered by beta-blockers. Most experience in treating thyrotoxicosis has been gained with propranolol hydrochloride but nadolol p. 161 is also used. Thyrotoxic crisis (‘thyroid storm’) requires emergency treatment with intravenous administration of fluids, propranolol hydrochloride and hydrocortisone p. 713 (as sodium succinate), as well as oral iodine solution and carbimazole or propylthiouracil which may need to be administered by nasogastric tube. Antithyroid drugs in pregnancy Radioactive iodine therapy is contra-indicated during pregnancy. Propylthiouracil and carbimazole can be given but the blocking-replacement regimen is not suitable. Carbimazole is associated with congenital defects, including aplasia cutis of the neonate, therefore propylthiouracil remains the drug of choice during the first trimester of pregnancy. In the second trimester, consider switching to carbimazole because of the potential risk of hepatotoxicity with propylthiouracil. Both propylthiouracil and carbimazole cross the placenta and in high doses may cause fetal goitre and hypothyroidism—the lowest dose that will control the hyperthyroid state should be used (requirements in Graves’ disease tend to fall during pregnancy). See also Important safety information in the carbimazole below drug monograph. Other drugs used for Hyperthyroidism Metoprolol tartrate, p. 166 ANTITHYROID DRUGS › SULFUR-CONTAINING IMIDAZOLES
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900 micrograms every 24 hours for 2 doses, dose
First-line fragment. Read the complete Indications and Dose section above.
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