Thyroid Function (TSH/FT3/FT4)
Type
Blood Testing
Biomarkers
3
Duration
30 min
Results
48 hours
Complete thyroid panel: TSH, Free T3, Free T4 to assess thyroid function. Results in 24 hours, no fasting required.
A thyroid panel evaluates how well your thyroid gland is functioning by measuring the hormones it produces and the pituitary signal that controls it. The thyroid is a butterfly-shaped gland in your neck that regulates metabolism, energy, body temperature, heart rate, and mood. A basic panel measures TSH (the brain's signal to the thyroid) and Free T4 (the main thyroid hormone). Comprehensive panels add Free T3 (the active hormone), reverse T3, and thyroid antibodies (TPOAb, TGAb) that can detect autoimmune conditions like Hashimoto's thyroiditis or Graves' disease. Thyroid dysfunction is extremely common — affecting roughly 1 in 8 women — and often goes undiagnosed because symptoms mimic stress, aging, or depression.
Key Details
Who Is This For?
Anyone experiencing unexplained fatigue, weight changes, hair loss, cold sensitivity, or mood disturbances. People with a family history of thyroid disease or autoimmune conditions. Women planning pregnancy, as thyroid function is critical for fetal brain development. Anyone who has had a 'normal' TSH result but still suspects thyroid dysfunction.
What's Included
Preparation Required
No fasting required for a standalone thyroid panel. If you take thyroid medication (levothyroxine/Synthroid), take your dose after the blood draw, not before — taking it beforehand can temporarily spike T4 levels and skew results. Morning testing is recommended for the most consistent TSH readings, as TSH follows a circadian rhythm and peaks overnight.
Biomarkers Tested
3The primary screening test for thyroid function. TSH is produced by the pituitary gland to regulate thyroid hormone production. High TSH indicates an underactive thyroid (hypothyroidism), while low TSH suggests an overactive thyroid (hyperthyroidism).
The unbound, active form of the main thyroid hormone T4. Free T4 directly reflects thyroid gland output and is used alongside TSH to diagnose and monitor thyroid disorders.
The active form of thyroid hormone responsible for regulating metabolism, energy, and body temperature. Free T3 is converted from T4 in tissues and is three to four times more potent than T4.
Where to get this
View on mapMore from iMedical Australia
Comprehensive Metabolic Panel
$57Essential metabolic screening including liver function, kidney function, cholesterol panel, fasting glucose, magnesium, and CRP inflammation marker. Results in 24-48 hours.
Check Up
$79Basic health screening with full blood count (FBC), ESR, liver function, kidney function, lipid profile, fasting glucose, magnesium, and CRP. Ideal first health check.
Check Up 2
$128Enhanced health check including FBC/ESR, liver/kidney function, lipids, glucose, magnesium, CRP plus vitamin D and HbA1c for diabetes screening.
General Check Up Plus
$148Comprehensive screening adding iron studies and full thyroid function (TSH, FT3, FT4) to standard metabolic panel for thorough health assessment.
- Category
- Diagnostic
- Sample Type
- Blood draw
- Duration
- 30 min
- Results
- 48 hours
iMedical Australia
Australia's largest direct access pathology service offering online blood test ordering with no GP referral needed. Results in 24-48 hours via email/SMS.