A 32 year old woman presents with fatigue, weight gain and cold intolerance. Examination shows dry skin and delayed ankle reflexes. TSH is 18 mIU/L (normal 0.4-4.0) and free T4 is low. What is the most appropriate management?AReassure and repeat thyroid function in 12 monthsBStart levothyroxine at a full replacement dose adjusted to weightCStart carbimazoleDRefer urgently for thyroid ultrasound and fine needle aspirationETreat with beta blockers aloneCheck my answer