Hyperthyreosis

Hyperthyreosis, also known as hyperthyroidism, is a disorder characterized by excess production and circulating levels of thyroid hormones T4 and T3, resulting in an increased metabolic rate. TSH is typically suppressed due to negative feedback.

Common causes include Graves' disease (autoimmune stimulation of the TSH receptor), toxic multinodular goiter, solitary toxic adenoma, thyroiditis (subacute, painless, postpartum), and, less commonly, excess iodine intake or certain drugs such as amiodarone.

Symptoms reflect increased metabolism: weight loss despite normal or increased appetite; heat intolerance; palpitations; tremor; anxiety; irritability; insomnia; sweating; menstrual changes. Overt Graves' disease can present with orbitopathy and, in some patients, eye findings.

Diagnosis relies on laboratory and imaging: suppressed TSH with elevated free T4 and/or free T3. Autoantibodies against the TSH receptor may support Graves'. Radioactive iodine uptake and scan help distinguish etiologies; thyroid ultrasound can identify nodules.

Treatment is tailored to cause and patient factors. Options include antithyroid drugs (methimazole or propylthiouracil), beta-blockers for symptomatic relief, radioactive iodine therapy, and thyroidectomy. In pregnancy, PTU is preferred in the first trimester; methimazole later. Long-term monitoring of thyroid function is needed after treatment due to risk of hypothyroidism or relapse.

Prognosis and complications: With appropriate therapy, most patients improve; untreated disease increases risk of atrial fibrillation, heart failure, bone loss, and miscarriage in pregnancy. Regular follow-up and dose adjustments are essential.