Lab test requirements · preparation, ID, referral, and timing United States · 0 communities
LabRequirements Know what your test requires

Mid-Atlantic · Reverse T3 Test – rT3 Testing

Reverse T3 Test – rT3 Testing in New Jersey

This page explains the reverse t3 test – rt3 testing, what it measures, and how to order it. The Reverse T3 blood test measures a form of thyroid hormone that can help clarify unusual thyroid function test results. It is often used alongside other thyroid tests to give a fuller picture of how the body is handling thyroid hormone.

Sample typeBlood and/or urine at a collection lab
ReferralIncluded — no referral from your own doctor needed

Lab requirements in New Jersey

Here is what you need before ordering and completing the Reverse T3 Test – rT3 Testing in NJ. Review each item and confirm the details with the collection lab.

Physician's order
Included. A physician's order is required for lab testing and is provided for you by our partner's physicians — no referral from your own doctor is needed.
Fasting
Some tests require fasting or avoiding certain foods or drinks beforehand. You will be informed when you order — confirm the details with the collection lab.
Preparation
Preparation instructions can vary depending on the laboratory and the other tests being performed at the same time. Always follow the specific instructions provided by the collection lab or…
Sample & visit
A blood and/or urine sample is collected; the visit usually takes about 10 minutes.
Identification
Bring the lab requisition form from your account. The collection lab may also ask for a government-issued photo ID.
Turnaround
1-3 business days
Availability
Our partner lab does not serve ND, RI, NY, NJ, MD or HI, including NJ. Confirm availability for your location with the collection lab.

Before you go

  • Order your test before visiting a lab, then use the requisition form in your account.
  • Print the requisition form, or fax it to the lab directly from your account.
  • No scheduling is needed — visit the collection lab during its normal business hours.
  • A blood and/or urine sample is collected; the visit usually takes about 10 minutes.
  • Bring a government-issued photo ID in case the lab requests it.
  • Results are posted to your secure account within 1–3 business days.

Requirements are summarized from our partner lab's published policies. Preparation and availability can change — confirm current instructions with the collection lab before your visit.

What this test is

Reverse T3 is a biologically inactive form of thyroid hormone produced when the body converts thyroxine (T4) in an alternative pathway. This test measures the amount of reverse T3 circulating in the blood. It is not a stand-alone diagnostic test but is interpreted with other thyroid hormone measurements.

What it measures

  • Reverse T3 — reflects the amount of this inactive thyroid hormone form in the blood
  • Total T3 — often measured alongside to assess active thyroid hormone levels
  • Free T4 — helps evaluate the main thyroid hormone produced by the thyroid gland
  • TSH — indicates how the pituitary gland is responding to thyroid hormone levels

What the test involves

A healthcare professional collects a small sample of blood, usually from a vein in your arm, using a standard blood draw. The sample is then sent to a laboratory for analysis.

Why it is often ordered

A clinician may order a reverse T3 test when thyroid test results are confusing or when a nonthyroidal illness is suspected. It is typically used to help evaluate whether symptoms or abnormal thyroid tests might be related to how the body is converting thyroid hormones.

Preparation

Preparation instructions can vary depending on the laboratory and the other tests being performed at the same time. Always follow the specific instructions provided by the collection lab or your healthcare provider.

How results are reported

Results are reported as a numeric value for reverse T3, and the laboratory will provide a reference range for comparison. Reference ranges can differ between laboratories because of differences in equipment, methods, and population, so your result should be interpreted using the range from the lab that performed the test.

Before you go

  • Whether any other tests will be drawn at the same time and if fasting is required.
  • The specific reference range used by the laboratory performing the test.
  • How and when you will receive your results.

Cities

Reverse T3 Test – rT3 Testing in New Jersey communities

Choose your city for local context and to order this test.

Trenton316,436Reverse T3 Test – rT3 TestingNewark306,247Reverse T3 Test – rT3 TestingJersey City287,146Reverse T3 Test – rT3 TestingAtlantic City236,314Reverse T3 Test – rT3 TestingPaterson157,927Reverse T3 Test – rT3 TestingElizabeth135,772Reverse T3 Test – rT3 TestingVineland92,364Reverse T3 Test – rT3 TestingClifton89,460Reverse T3 Test – rT3 TestingCamden72,381Reverse T3 Test – rT3 TestingBayonne70,553Reverse T3 Test – rT3 TestingPassaic70,308Reverse T3 Test – rT3 TestingEast Orange68,918Reverse T3 Test – rT3 TestingUnion City67,903Reverse T3 Test – rT3 TestingTwin Rivers64,012Reverse T3 Test – rT3 TestingHoboken59,369Reverse T3 Test – rT3 TestingNew Brunswick55,671Reverse T3 Test – rT3 TestingPerth Amboy55,046Reverse T3 Test – rT3 TestingPlainfield54,183Reverse T3 Test – rT3 TestingWest New York52,485Reverse T3 Test – rT3 TestingSicklerville46,626Reverse T3 Test – rT3 TestingHackensack45,723Reverse T3 Test – rT3 TestingSayreville45,062Reverse T3 Test – rT3 TestingLinden43,387Reverse T3 Test – rT3 TestingKearny41,790Reverse T3 Test – rT3 TestingFort Lee39,701Reverse T3 Test – rT3 TestingFair Lawn34,820Reverse T3 Test – rT3 TestingGarfield32,481Reverse T3 Test – rT3 TestingLong Branch31,734Reverse T3 Test – rT3 TestingWestfield30,950Reverse T3 Test – rT3 TestingPrinceton30,717Reverse T3 Test – rT3 TestingRahway29,582Reverse T3 Test – rT3 TestingEnglewood29,129Reverse T3 Test – rT3 TestingBergenfield28,282Reverse T3 Test – rT3 TestingMillville27,946Reverse T3 Test – rT3 TestingParamus26,650Reverse T3 Test – rT3 TestingRidgewood25,991Reverse T3 Test – rT3 TestingLodi25,983Reverse T3 Test – rT3 TestingCliffside Park25,515Reverse T3 Test – rT3 TestingCarteret25,077Reverse T3 Test – rT3 TestingSomerset24,827Reverse T3 Test – rT3 TestingSouth Plainfield24,251Reverse T3 Test – rT3 TestingNorth Plainfield22,635Reverse T3 Test – rT3 TestingSummit22,598Reverse T3 Test – rT3 TestingRoselle22,511Reverse T3 Test – rT3 TestingHillsborough22,273Reverse T3 Test – rT3 TestingParsippany21,931Reverse T3 Test – rT3 TestingSecaucus21,439Reverse T3 Test – rT3 TestingElmwood Park21,239Reverse T3 Test – rT3 TestingLindenwold21,048Reverse T3 Test – rT3 TestingPleasantville20,505Reverse T3 Test – rT3 TestingPalisades Park20,291Reverse T3 Test – rT3 TestingGlassboro20,284Reverse T3 Test – rT3 TestingMorristown20,003Reverse T3 Test – rT3 TestingHawthorne19,507Reverse T3 Test – rT3 TestingPreakness19,083Reverse T3 Test – rT3 TestingTinton Falls19,053Reverse T3 Test – rT3 TestingPoint Pleasant18,839Reverse T3 Test – rT3 TestingHarrison18,824Reverse T3 Test – rT3 TestingRutherford18,781Reverse T3 Test – rT3 TestingColonia18,776Reverse T3 Test – rT3 Testing