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 heparin administration.
- Turnaround: 4-6 days (may take longer based on weather, holiday, or lab delays)
What's Included
Thyroid Panel with TSH
- Thyroid-Stimulating Hormone (TSH): Produced by the pituitary gland to stimulate thyroid hormone production. Helps identify an underactive or overactive thyroid.
- T3 Uptake: Part of the comprehensive thyroid hormone evaluation included in this panel.
- T4 (Thyroxine), Total: Measures total thyroxine, a primary thyroid hormone, as part of this comprehensive evaluation.
- Free T4 Index (T7): A calculated value used alongside T3 Uptake and T4 to evaluate thyroid hormone status.
Free Thyroid Hormones
- Triiodothyronine (T3), Free: Represents about 5% of circulating thyroid hormone. Useful for confirming hyperthyroidism when thyroxine levels are elevated. Not affected by carrier protein variation.
- Thyroxine (T4) Free (Direct): The active form of thyroxine. Considered a more accurate reflection of thyroid hormone function than total T4, and is commonly used in place of it.
Reverse T3
- Reverse T3, Serum: A biologically inactive form of T3. Levels can rise during stress, severe illness, injury, or with certain drugs (such as amiodarone and glucocorticoids). Most informative when evaluated alongside Free T3 to assess the ratio between the two.
Benefits
- Evaluates thyroid hormone production and regulation in one panel.
- Includes both total and free thyroid hormone measurements.
- Assesses Reverse T3 alongside Free T3 for a fuller picture.
- Supports evaluation of pituitary gland function through TSH.
- Helps assess thyroid disorder severity and monitor treatment.
Who Is This Test For?
- Individuals noticing possible signs of thyroid imbalance.
- People wanting a broader view of thyroid hormone conversion, including Reverse T3.
- Those monitoring existing thyroid treatment or management.
- Individuals working with a healthcare provider to assess pituitary and thyroid function together.
- People wanting a fuller thyroid hormone picture than a basic TSH test alone.
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 offers a detailed look at thyroid function by combining a comprehensive thyroid hormone panel (TSH, T3 Uptake, Total T4, and Free T4 Index) with Free T3, Free T4, and Reverse T3. Together, these biomarkers help evaluate how well your thyroid is producing and converting hormones, and how your pituitary gland is signaling that process. This panel is not intended to diagnose a condition on its own.
2. Who would benefit from this test?
This panel may be useful for individuals who want a more complete view of their thyroid hormone activity, including how T4 converts to active and inactive hormone forms. It can also be of interest to those already being monitored for thyroid-related concerns who want additional context beyond a standard thyroid screen.
3. When should I order this panel?
You might consider this panel if you want a broader evaluation of thyroid hormone levels and conversion, or if you are following up on a previous thyroid-related result. It can also be useful when monitoring thyroid status over time in coordination with a healthcare provider. This panel does not diagnose a 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 4-6 days. This may take longer based on weather, holiday, or lab delays.
6. How do I interpret the results?
Thyroid hormone levels are often most meaningful when viewed together as a pattern rather than as isolated numbers. For example, comparing Reverse T3 to Free T3 can offer more context than either value alone. Discuss your specific results with a healthcare provider who can interpret them in light of your health history.
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?
Share your results with a healthcare provider, who can help interpret them alongside your symptoms and health history. They can help determine whether further testing, monitoring, or treatment adjustments may be appropriate.
8. How often should I get tested?
Testing frequency depends on your individual health circumstances. Follow up as directed by your healthcare provider, particularly if you are monitoring an existing thyroid concern or ongoing treatment.
9. Why early detection matters
Understanding your thyroid hormone levels, including how T4 converts to active and inactive forms, may support earlier awareness of changes in thyroid function. Ongoing monitoring, guided by a healthcare provider, can help you stay informed about your thyroid health over time.
Pre-test preparation
No fasting is required. Patient should stop biotin consumption at least 72 hours prior to the collection. Collection should not occur during or after administration of heparin.
