Quick Facts
- Sample: Blood
- Fasting: No fasting is required. Stop biotin consumption at least 72 hours prior to collection. Collection should not occur during or after administration of heparin.
- Turnaround: 1-2 days. May take longer based on weather, holiday, or lab delays.
What's Included
Thyroid Function Tests
- T4 Free (Direct): Measures the active form of thyroxine, offering an accurate reflection of your thyroid hormone function.
- TSH (Thyroid-Stimulating Hormone): Helps assess thyroid function, monitor thyroid replacement therapy, and screen for thyroid disorders.
Benefits
- Evaluates two key markers of thyroid hormone function.
- Helps screen for hyperthyroidism and hypothyroidism.
- Supports monitoring of thyroid hormone replacement therapy.
- Convenient blood test with fast turnaround.
- No fasting required before testing.
Who Is This Test For?
- You want a general check of your thyroid hormone function.
- You are experiencing symptoms that may relate to thyroid imbalance.
- You take thyroid hormone medication and want to monitor your levels.
- You and your healthcare provider want to evaluate thyroid feedback function.
- You are interested in routine thyroid screening.
How It Works
- Order Your Test Online
- Visit a Local Lab
- Get Results Online
FAQ
1. What is the purpose of this test?
This panel measures T4 Free (Direct) and TSH, two biomarkers that work together to reflect thyroid hormone function. T4 Free shows how much active thyroid hormone is available, while TSH shows how the pituitary gland is signaling the thyroid. Together, these results can help evaluate healthy thyroid function and screen for possible thyroid disorders.
2. Who would benefit from this test?
This test may benefit individuals interested in a general evaluation of thyroid hormone function, those experiencing symptoms that may be related to thyroid imbalance, and individuals taking thyroid hormone medication who want to monitor their levels over time. It may also suit those interested in routine thyroid screening.
3. When should I order this panel?
You may consider ordering this panel as part of general thyroid screening, to monitor known thyroid hormone therapy, or as a follow-up when tracking thyroid hormone levels over time. This panel does not diagnose a specific condition on its own.
4. Do I need to fast before this test?
No fasting is required. Stop biotin consumption at least 72 hours prior to collection. Collection should not occur during or after administration of heparin.
5. How quickly will I get results?
Results are typically available in 1-2 days. May take longer based on weather, holiday, or lab delays.
6. How do I interpret the results?
Thyroid biomarkers are often most meaningful when viewed together rather than individually, since T4 Free and TSH can reflect different aspects of thyroid function. Patterns across both results can offer more context than a single value alone. Always discuss your results with a healthcare provider for proper interpretation.
Disclaimer: Reference ranges may vary by laboratory. Listed ranges are general guidelines and may differ from those used by the performing lab. Always consult your healthcare provider for interpretation.
7. What should I do if my results are abnormal?
If your results fall outside the expected range, discuss them with your healthcare provider. They can help determine whether further testing or follow-up care may be appropriate based on your individual health history.
8. How often should I get tested?
Testing frequency depends on your individual health needs. Retesting may be considered as directed by your healthcare provider, particularly if you are monitoring thyroid hormone therapy or ongoing symptoms.
9. Why early detection matters
Monitoring thyroid hormone function over time may support earlier awareness of changes in thyroid activity. Staying informed about your T4 Free and TSH levels can help you and your healthcare provider have more meaningful conversations about your thyroid health.
Pre-test preparation
No fasting is required. Patients should stop biotin consumption at least 72 hours prior to the collection. Collection should not occur during or after administration of heparin.
Do not stop prescribed medication unless instructed by your healthcare provider.
