Comments : -The dose should be individualized on the basis of clinical response and biochemical tests. Regular monitoring of TSH and thyroxine is recommended when starting therapy or changing the dose.
Pregnancy and lactation Thyroxine requirements increase by 25-30 during pregnancy with increased requirements seen as early as the fifth week of pregnancy. 6 Children born to women whose hypothyroidism was inadequately treated in pregnancy are at increased risk of neuropsychological impairment.
They can also facilitate physician-patient discussions. Drug Monographs More than 7100 monographs are provided for prescription and over-the-counter drugs, as well as for corresponding brand-name drugs, herbals, and supplements. Drug images are also included.
Doses greater than 200 mcg/day orally are seldom required. An inadequate response to oral daily doses of 300 mcg/day or greater is rare and may indicate poor compliance, malabsorption, and/or drug interactions -FOR MOST PATIENTS OLDER THAN 50 YEARS OR FOR PATIENTS UNDER 50 YEARS OF AGE WITH UNDERLYING CARDIAC DISEASE : -Initial dose: 25.
Lifelong thyroxine therapy relieves symptoms and restores 'normal' thyroid function. Commencing thyroxine can aggravate cardiac disease but is relatively free of adverse effects. The concentration of thyroid stimulating hormone is used to monitor therapy.
When commencing thyroxine in secondary hypothyroidism it is therefore safest to also treat the patient with a corticosteroid (for example prednisone 5 mg daily). Subsequently, cortisol reserve can be assessed with an early morning cortisol measurement.
Generally, TSH is suppressed to less than 0.1 international units per liter (mU/L and this usually requires a dose of greater than 2 mcg/kg/day. However, in patients with high-risk tumors, the target level for TSH suppression may be less than 0.01 mU/L.
7 I advise women taking thyroxine who are planning to conceive to increase their dose of thyroxine by 30 at the confirmation of the pregnancy. TSH should be monitored every 8-10 w.
Treatment Primary hypothyroidism is treated by giving the patient replacement thyroxine, usually for life. Liothyronine rarely needs to be used unless there is life-threatening hypothyroidism. Alternative sources of thyroid hormones such as thyroid extracts should be avoided.
Secondary hypothyroidism occurs with some pituitary and hypothalamic diseases. Diagnosis Patients may not present with the typical clinical features of hypothyroidism. They may have vague symptoms such as tiredness. The diagnosis can be made by finding a persistently elevated serum concentration of thyroid stimulating hormone (TSH).
Otherwise healthy patients who have recently undergone thyroidectomy or radioiodine treatment for thyrotoxicosis can immediately start at or just below their predicted daily replacement dose of thyroxine 100-200 microgram. Elderly patients and those with known heart disease should start with a daily dose of thyroxine 25 microgram for 3-4 weeks with a reassessment of their.
When the thyroxine dose is in the range of 100-200 microgram/day, variable daily dosing may be necessary to achieve euthyroidism. Considering the total weekly dose is helpful when changing the dose.
It is extremely important to consider cortisol deficiency before starting treatment with thyroxine in patients with pituitary and hypothalamic disease as its use will speed the metabolism of cortisol and can induce an adrenal crisis.