- Serum or plasma fT4 and TSH concentrations should be determined between 8-9 am before the morning dose of L-T4.
- First follow up visit – fT4 should be checked 2 weeks after starting thyroxine and adjust the dose accordingly.
- fT4 concentration should be maintained in the upper half of the age specific reference range.
- TSH should be maintained in the age specific reference range.
- Any reduction of L-T4 dose should not be based on a single increase in fT4 concentration during treatment.
Once TSH/fT4 levels have normalized the suggested follow up is as follows –
During first 6 months of life ® fT4 and TSH should be checked every 6 weeks
6 months to 12 months of life ® fT4 and TSH should be checked every 8 weeks
1 year to 3 years of life ® fT4 and TSH should be checked every 3 months
After 3 years till growth is completed ® fT4 and TSH should be checked every 6-12 months.
- Additional evaluations should be carried out 4–6 weeks after any change in L-T4 dose.
- Adequate treatment throughout childhood is essential for normal growth and development.
- Over-treatment should be avoided.
- Anthropometry including skull circumference (OFC) measurements and development should be monitored at each clinic visit.