Thyroid Stimulating Hormone (TSH)
The single best screening test for thyroid function, and the one used to adjust a thyroxine dose
Also known as TSH, Thyroid stimulating hormone, Thyroid screen, TSH (Thyroid Stimulating Hormone), Thyroid Profile Test (TFT)
₹125/-₹250/-50% offFree collection on orders above ₹500/-
- Reports within
- 8 hours
- Parameter included
- 01see list
- Sample
- Blood
- Fasting
- Not needed
- Measures
- Level of thyroid stimulating hormone in the blood
- Identifies
- Underactive thyroid (hypothyroidism), overactive thyroid (hyperthyroidism), and whether a thyroxine dose is right
Collected at home
A trained phlebotomist visits at a time you pick, from the next hour
Sealed single-use kit
Opened in front of you, and carried to the lab under controlled conditions
Report within 8 hours
On WhatsApp and email, with any value outside the normal range highlighted
What is the TSH test?
TSH, or thyroid stimulating hormone, is made by the pituitary gland at the base of the brain. It tells the thyroid gland in the neck how much thyroid hormone to make. The test measures the level of TSH in your blood, in micro-international units per millilitre.
TSH works in reverse to what most people expect. When the thyroid is underactive, the pituitary pushes harder and TSH goes up. When the thyroid is overactive, the pituitary eases off and TSH falls. That makes it the single most sensitive screening test for thyroid trouble, and the number a doctor uses to set or adjust a thyroxine dose. If TSH is out of range, the doctor will usually add free T4 and T3 to see the full picture.
No fasting is needed. A morning sample is preferred because TSH is naturally a little higher early in the day, and repeating at the same time each visit makes results comparable. The sample is collected at home and the report arrives in 8 hours.
TSH parameters1 measured
TSH
0.55–4.78 µIU/mL
Thyroid stimulating hormone, the pituitary's signal to the thyroid, rising when the thyroid is underactive and falling when it is overactive
Reference ranges are the lab's defaults for adults and are printed on the report beside every value
How to prepare
- No fasting is needed.
- Book a morning slot if you can, and use the same time of day for repeat tests.
- Stop biotin or multivitamins containing biotin for 48 hours before the sample, as biotin interferes with the assay.
- If you take thyroxine, take it after the sample is collected unless your doctor says otherwise.
Who should take it
Anyone with tiredness, weight change, hair fall, dry skin, constipation, palpitations, tremor or swelling in the neck. Women planning a pregnancy or in the first trimester, and women with irregular periods or difficulty conceiving. Anyone already on thyroxine or anti-thyroid tablets, for dose monitoring. People with a parent or sibling with thyroid disease, or with type 1 diabetes or another autoimmune condition. Adults over 50 as part of a routine check, and anyone whose cholesterol has risen without an obvious reason.
Before the visit
Tell your doctor about steroids, lithium, amiodarone, dopamine and biotin, and about any recent serious illness or hospital stay, as all of these shift TSH. Pregnancy uses different reference ranges, so mention it on the report request.
Why take the TSH test?
- Unexplained weight change: gaining weight while eating the same, or losing it without trying, is a classic thyroid sign.
- Tiredness and cold: constant fatigue, feeling cold when others are fine, dry skin and hair fall often trace back to a high TSH.
- Racing heart or anxiety: palpitations, tremor, sweating and poor sleep can point to a low TSH.
- Irregular periods or trouble conceiving: thyroid imbalance is a common and easily treated cause, and it is checked early in pregnancy.
- Dose check on thyroxine: anyone on thyroid tablets needs TSH rechecked six to eight weeks after a dose change, then every six to twelve months.
Questions about the TSH test
What is a TSH test used for?
It is the first test for thyroid problems. A high TSH usually means an underactive thyroid and a low TSH an overactive one. It is also the number used to adjust the dose in people taking thyroxine.
Do I need to fast for a TSH test?
No fasting is needed. A morning sample is preferred because TSH is naturally a little higher early in the day, and stop biotin supplements for 48 hours before, as biotin interferes with the test.
What sample is taken and how does home collection work?
A small blood sample from the arm. A trained phlebotomist visits your home with a sealed single-use kit and takes the sample to the lab. Choose an early slot if you want a morning reading.
What is the normal TSH range?
The reference range on the report is 0.55 to 4.78 µIU/mL for adults who are not pregnant. Pregnancy has its own lower ranges by trimester, so tell your doctor if you are pregnant.
What does a high or low TSH mean?
High TSH means the thyroid is not making enough hormone, so the pituitary is pushing harder; this is hypothyroidism. Low TSH means the thyroid is overactive, or a thyroxine dose is too high. Either way, your doctor will usually add free T4 and T3 before deciding.
Who should get TSH tested and how often?
Anyone with tiredness, weight change, hair fall, palpitations, neck swelling or irregular periods, and women planning or early in pregnancy. People on thyroxine recheck six to eight weeks after a dose change, then every six to twelve months.
How long does the TSH report take?
The report reaches your WhatsApp and email in 8 hours from collection. If your doctor has also asked for free T4 or T3, those come from the same sample and arrive with it.
Can I take my thyroid tablet before the TSH test?
Take it after the sample is collected, unless your doctor has said otherwise. Thyroxine taken just before the sample can nudge the result, and most doctors want TSH measured before the morning dose. Do not skip the dose altogether.
Commonly tested together
Often on the same prescription
What happens after you book
- A phlebotomist is assigned and reaches you in your chosen slot, as soon as the next hour
- The sample is collected with a sealed single-use kit and moved on a cold chain
- The report lands on WhatsApp and email within 8 hours