Hyperthyroidism in pregnancy

Mestman JH. Hyperthyroidism in pregnancy. Endocrinol Metab Clin North Am 1998 27 127. 

Inzucchi SE. Hyperthyroidism in pregnancy. Curr Ther Endocrinol Metab 1997 6 312-7. 

Atkins P, Cohen SB, Phillips BJ. Drug therapy for hyperthyroidism in pregnancy Safety issues for mother and fetus. Drug Saf 2000 23 229-244. 

Radiation destruction of thyroid parenchyma Hyperthyroidism patients should be euthyroid or on blockers before RAI avoid in pregnancy or in nursing mothers Oral half-life 5 days onset of 6-12 weeks maximum effect in 3-6 months Toxicity Sore throat, sialitis, hypothyroidism... 

Neonatal hypothyroidism has been reported after maternal use of antithyroid drugs (106,107). Transient neonatal hyperthyroidism in a female child born to a mother who had been treated with potassium iodide and carbimazole during pregnancy was followed by sexual precocity (108). 

Half-life. Plasma half-life, 6 to 7 days which may be increased in pregnancy or myxoedema and decreased in hyperthyroidism. 

Differential diagnosis Palmar erythema is also found in pregnancy, in hyperthyroidism, collagen diseases, endocarditis, long-standing feverish conditions, tuberculosis, diabetes mellitus, malignant tumours, chronic polyarthritis and in cases of malnutrition — as well as in healthy people. 

A deficiency or surfeit of certain hormones can influence the activity of the enzymes involved in drug biotransformation. Apart from the sex hormones, those of the adrenal, pancreas, pituitary, and thyroid also exert effects on the regulation of certain enzyme activities. Some hormonal disease states, such as diabetes and hyperthyroidism, could have important implications for drug biotransformation. Alterations in drug biotransformation can occur in pregnancy, and this subject area requires much more study. 

Propylthiouracil crosses the placenta as readily as the thioimidazoles, but the rare and probably real association between thioimidazoles and fetal anomalies makes the thioimidazoles less attractive first-line alternatives (81-83). When propylthiouracil is used cautiously in minimal amounts and with frequent dose adjustments, it is probably the safest form of treatment of hyperthyroidism during pregnancy (SEDA-8,373) (SEDA-11, 357). 

Propranolol (Inderal) P adrenergic receptor antagonist. Suppresses tachycardia and other catecholamine effects. Emergent preparation of hyperthyroid patients for surgery. Thyrotoxicosis in pregnancy. Thyroid storm. CNS sedation and depression. Suppression of failing heart. 

Iodine excess may cause thyroid dysfunction, such as hypothyroidism or hyperthyroidism, in humans. Although no direct developmental toxic effect of excess iodine was reported in humans, the body of evidence that maternal thyroid dysfunction may result in adverse pregnancy outcome is increasing. An in vitro study (Harakawa et al., 1989) investigated the effects of excess or deficiency of TH on early embryogenesis in rat embryo culture. The results showed that malformations, including open... 

Iodine is found in the blood as inorganic and protein-bound iodine, the latter fraction probably representing the circulating thyroid hormone. The total iodine content of normal whole blood is about 8 to 12 /xg. per 100 ml. (range 3 to 30 /xg.) protein-bound iodine varies from 3 to 8 /xg. per 100 ml., with a mean of 5 to 6 /xg. (Chapter 22). The level of protein-bound iodine is increased in pregnancy and in hyperthyroidism and decreased in hypothyroidism. 

The drug is contraindicated in die presence of an allergy to die drug, pregnancy (Category C), lactation, and phenylketonuria (oral form only). Linezolid is used cautiously in patients with bone marrow depression, hepatic dysfunction, renal impairment, hypertension, and hyperthyroidism. 

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