Mrs Hopkins is a 55 year old lady who presents to the GP with a 3 month history of fatigue and dry skin. She denies any pruritus or rash. There are no abdominal pain, bowel or urinary symptoms. Initial blood tests are done to investigate feeling tired all the time and are as followed:
Initial bloods reveal:
Haemoglobin 120g/L
Serum sodium 138 mmol/l
Serum potassium 5 mmol/l
Serum urea 5.5 mmol/l
Serum creatinine 110 µmol/L
TSH 8.5 mU/L
Free T3 5 pmol/L
Free T4 12 pmol/L
Based on her likely diagnosis, what would be the most appropriate management option for her?