My child's TSH is slightly high: now what?
A test result just outside the range worries families. Most of the time it means repeating the test, not starting medicine.
TSH is a hormone from the brain that tells the thyroid to work. When the thyroid works too little, TSH rises. That is why a high result looks worrying, but a slightly high TSH is not always an illness.
Why might it be slightly high?
- Normal variation or a recent illness
- The reference range differs with a child’s age
- Excess weight, which can itself raise TSH a little
- The start of autoimmune thyroid disease
What is the next step?
The doctor usually looks at T4 and repeats the test after a few weeks to a few months. Sometimes thyroid antibodies are checked too. In an older child with a slightly high TSH, normal T4, good growth and no symptoms, follow-up without medicine is often enough, and in many children the result becomes normal on its own.
When does medicine come up?
- T4 is low or TSH has risen a lot
- Growth has slowed or there are signs of an underactive thyroid
- A goitre, or positive antibodies alongside other results
- Other conditions that concern the doctor
Newborns are different
This article is for older children. A newborn with a high screening result needs follow-up the same day, because thyroid hormone matters for the growing brain. Read thyroid conditions in children.
Before the next test
Tell the doctor about any supplement. Biotin, found in some hair and nail supplements, can upset the test result. Do not start or stop thyroid tablets without the doctor.