follow-up for hyperthyroidism

Last edited 12/2019 and last reviewed 08/2021

Follow-up and monitoring of hyperthyroidism

Monitoring after radioactive iodine treatment

• consider measuring TSH, FT4 and FT3 levels in adults, children and young people every 6 weeks for the first 6 months after radioactive iodine treatment until TSH is within the reference range.
• for adults, children and young people who have hypothyroidism after radioactive iodine treatment and are not on antithyroid drugs, offer levothyroxine replacement therapy and with dosage and monitoring as per management of primary hypothyroidism
• for adults, children and young people with TSH in the reference range 6 months after radioactive iodine treatment, consider measuring TSH (with cascading) at 9 months and 12 months after treatment.
• for adults, children and young people with TSH in the reference range 12 months after radioactive iodine treatment, consider measuring TSH (with cascading) every 6 months unless they develop hypothyroidism (then follow advice above)

If hyperthyroidism persists after radioactive iodine treatment in adults, children and young people, consider antithyroid drugs[2] until the 6-month appointment.

If hyperthyroidism persists 6 months after radioactive iodine treatment in adults, children and young people, consider further treatment

Monitoring after surgery

Offer levothyroxine to adults, children and young people after a total thyroidectomy with dosage and monitoring as per management of primary hypothyroidism

Consider measuring TSH and FT4 at 2 and 6 months after surgery, and then TSH (with cascading) once a year for adults, children and young people who have had a hemithyroidectomy

Monitoring of antithyroid drugs

For adults, children and young people who are taking antithyroid drugs for hyperthyroidism, consider measuring:

• TSH, FT4 and FT3 every 6 weeks until their TSH is within the reference range,
• then TSH (with cascading) every 3 months until antithyroid drugs are stopped.

Do not monitor full blood count and liver function for adults, children and young people taking antithyroid drugs for hyperthyroidism unless there is a clinical suspicion of agranulocytosis or liver dysfunction.

For adults who have stopped antithyroid drugs, consider measuring:

• TSH (with cascading) within 8 weeks of stopping the drug,
• then TSH (with cascading) every 3 months for a year,
• then TSH (with cascading) once a year

For children and young people who have stopped antithyroid drugs, consider measuring:

• TSH, FT4 and FT3 within 8 weeks of stopping the drug,
• then TSH, FT4 and FT3 every 3 months for the first year,
• then TSH (with cascading) every 6 months for the second year,
• then TSH (with cascading) once a year

Reference:

• NICE (November 2019). Thyroid disease: assessment and management