Myxedema treatment

Myxedema and goiter are the main conditions for which thyroid preparations are indicated. The treatment of cretinism is difficult because it is recognized only at or after birth. Even if this disease could be diagnosed m utero, thyroid hormones do not readily cross the placental barrier. In addition, the fetus, as does a premature infant, rapidly deactivates the thyroid hormones. The halogen-free analogue DlMlT [26384-44-7] (3), which is resistant to fetal deiodinases, may prove useful for fetal hypothyroidism (cretinism). 

The treatment of myxedema coma can include which of the following agents ... 

Hypothyroidism (myxedema) results when there is a breakdown of thyroid hormone production in the thyroid gland. Treatment consists of replacing this hormone with aforementioned drugs. Treatment with levothyroxine, 3,5,3, 5 -tetraiodothyronine, is preferred. Lyothyronin, L-3,5,5 -triiodothyronine, is also used, as is lotrix, a mixture of levothyroxine and levothyronine in a 4 1 ratio. Of the drugs of animal origin, thyroidin and thy-roglobulin (proloid) are used. 

Myxedema coma/precoma (injection oniy) For the treatment of myxedema coma/precoma. 

An initial IV dose ranging from 25 to 50 meg is recommended in the emergency treatment of myxedema complications in adults. In patients with known or suspected cardiovascular disease, an initial dose of 10 to 20 meg is suggested. 

Herpes simplex virus encephalitis after myxedema coma has been described in an 81-year-old man treated with hydrocortisone (100 mg 8-hourly) and levothyroxine (328). In renal transplantation, two cases of death from Herpes simplex as a result of glucocorticoid treatment are on record (SED-8, 827 SEDA-17, 449). 

Liothyronine is used in the treatment of hypothyroidism, nontoxic goiter, cretinism, and myxedema. 

Thyroid extract is used in the treatment of hypothyroidism, myxedema, and cretinism. It is also used as a diagnostic agent and for suppression of pituitary thyroid-stimulating hormone. Synthetic derivatives are preferred because of uniform potency. 

Levothyroxine is indicated in the treatment of hypothyroidism (0.05 mg initially) of myxedema coma (0.4 mg IV initially) of thyroid-stimulating hormone (TSH) suppression in thyroid cancer of euthyroid and nodules goiter and of thyroid suppression therapy (2.6 mcg/kg/day for 7 to 10 days). Levothyroxine increases the metabolic rate of tissue. It affects protein and carbohydrate metabolism, promotes gluconeogenesis, increases the utilization and mobilization of glycogen stores, stimulates protein synthesis, and regulates cell growth and differentiation. The orally administered... 

Liothyronine sodium is a thyroid hormone that increases metabolic rate of body tissues and is needed for normal growth and maturation. It is indicated for the replacement or supplemental therapy in hypothyroidism in TSH suppression for treatment or prevention of euthyroid goiters (e.g., thyroid nodules, multinodular goiters, enlargement in chronic thyroiditis) and as a diagnostic agent in suppression tests to differentiate suspected hyperthyroidism from euthyroidism and in treatment of myxedema coma/precoma (IV). 

Myxedema coma is the extreme expression of severe, long-standing hypothyroidism. In addition to supportive care and treatment of the precipitating cause, treatment with thyroid hormone is essential. Based on uncertain oral absorption, thyroid hormone generally is given parenterally (e.g., a loading dose of200-300 pug ofl T i intravenously followed by a second dose of 100 ptg 24 hours later). A daily maintenance dose is then continued intravenously until the patient has improved sufficiently for oral therapy. Because of its more rapid onset of action, some clinicians add L-T ... 

In elderly patients, especially those with multisystemic diseases, hypothyroidism may become severe and fife threatening. Myxedema coma represents the most extreme form of severe hypothyroidism. This medical emergency may occur when severe hypothyroidism is complicated by trauma, infection, myocardial infarction, cold exposure, or administration of hypnotics or opiates, medications that suppress central nervous system function, particularly ventilatory drive. It typically presents in older women in winter. The main clinical features are hypothermia and a variable degree of altered consciousness (Iglesias et ai, 1999). Serum T4, TSH and cortisol should be measured to confirm the diagnosis and evaluate adrenal reserve. When there is a reasonably high level of suspicion, treatment should not be delayed to await laboratory results. 

Supportive measures, glucocorticoids and thyroid hormone administration are the keystones of treatment for patients with myxedema coma. 

Braverman L.E., Woeber K.A., Ingbar S.H. 1969 Induction of myxedema by iodide in patients euthyroid after radioiodine or surgical treatment of diffuse toxic goiter. New Engl.J.Med. 15 816-821. 

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