2nd May 2024

A 38-year-old man presents with a 3-month history of increased irritability, heat intolerance, and unintentional weight loss despite a good appetite.

A 38-year-old man presents with a 3-month history of increased irritability, heat intolerance, and unintentional weight loss despite a good appetite. He has a past medical history of hypertension, controlled with medication. On examination, he has a fine tremor, a resting heart rate of 98 bpm, and a diffusely enlarged, non-tender thyroid gland without nodules.

Investigations:

Free T4: 40 pmol/L (normal range: 12-22 pmol/L)

TSH: <0.01 mU/L (normal range: 0.4-4.0 mU/L)

Thyroid peroxidase antibodies: Negative

Which is the most appropriate initial management for his condition?