"The media love villains and magic bullets: the thyroid tends to be a favourite on both counts. Patient perceptions, especially regarding the thyroid and weight, can be very difficult to change, given the amount of media misinformation."
The goals of treatment for hypothyroidism are normalisation of TSH levels and relief of symptoms.8 For patients with diagnosed overt hypothyroidism recommended first-line treatment is thyroid hormone replacement at an initial dose of levothyroxine 50–100 micrograms /day, or 25 micrograms/day for frail or elderly patients.28 Current recommendations are that patients should have TSH and T4 retested 6–8 weeks after initiating levothyroxine to determine if a change in dosage is required. Non-adherence to treatment is the most common explanation for persistent elevations in TSH.8
For hyperthyroidism, choice of treatment depends on the patient’s age, symptoms, comorbidities and the underlying cause of illness.8,29 Most symptomatic patients, regardless of the cause of their condition, benefit from beta blockers to manage their adrenergic symptoms.30
Graves disease can be treated with antithyroid medicines (thionamides, which inhibit thyroid peroxidase), radioactive iodine or surgery. Since many patients with Graves disease who are treated with thionamides experience remission, medicines can be trialled initially, with alternatives sought for non-responders.31
After prescribing antithyroid medicine, refer patient to an endocrinologist. Patients who respond well to antithyroid medicines can complete an 18-month course of treatment. A reduction in dosage should be considered for patients who have a decrease in serum T3 and T4 at their 3–4-week follow-up. For longer-term maintenance therapy, monitoring will depend on the clinical situation of the individual patient. Some patients reach hypothyroid state quickly and will need frequent assessment. It is currently recommended that for these patients, thyroid function should be reviewed every 4 weeks.14
Radioactive iodine or thyroidectomy are the primary treatment options for toxic nodular goitre.8
Patients with milder subclinical hyperthyroidism often stabilise without treatment, so careful monitoring and repeat testing may be all that is required (see NPS MedicineWise Adult Thyroid Testing Algorithm for further information).8 Treatment should also be considered for symptomatic elderly patients, patients with underlying cardiovascular disease, and those with symptoms suggestive of hyperthyroidism or associated comorbidities.13
Accelerated bone loss is also related to hyperthyroidism. When TSH is less than 0.1 mIU/L, refer patient to an endocrinologist. A bone density scan may be considered to assess for osteoporosis as this can influence the decision to treat the thyroid.32
Less common causes of hyperthyroidism, such as subacute thyroiditis and amiodarone thyroiditis, are best managed by a specialist.
‘The decision to refer a patient with hyperthyroidism will depend on the experience of the GP managing this condition and the severity of the hyperthyroidism,’ says Professor Hamblin. ‘In contrast to hypothyroidism, most patients with hyperthyroidism are appropriately referred to an endocrinologist or consultant physician.’