ADULT, INITIALLY 50 - 100 MICROGRAMS DAILY, PREFERABLY BEFORE BREAKFAST, ADJUSTED IN STEPS OF 25 - 50 MICROGRAMS EVERY 3 - 4 WEEKS UNTIL METABOLISM NORMALISED (USUALLY 100 - 200 MICROGRAMS DAILY); IN CARDIAC DISEASE, SEVERE HYPOTHYROIDISM, AND PATIENTS OVER 50 YEARS, INITIALLY 25 MICROGRAMS DAILY OR 50 MICROGRAMS ON ALTERNATE DAYS, ADJUSTED IN STEPS OF 25 MICROGRAMS EVERY 4 WEEKS