Monitoring
Due to the long half-life of levothyroxine (1 week), thyroid-stimulating hormone (TSH) should be measured 4 to 12 weeks after initiation of therapy or dosage change.[1][8] Stable patients with normal serum TSH should have TSH measured every 12 months.[1][8] Pregnancy increases thyroid hormone requirements and the dose of levothyroxine may increase accordingly. TSH should be measured every 4 to 6 weeks in pregnant women on levothyroxine therapy until mid-gestation, then once in each of the second and third trimesters.[30][53]
Use of this content is subject to our disclaimer