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Midwest · Reverse T3 Test – rT3 Testing

Reverse T3 Test – rT3 Testing in North Dakota

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 North Dakota

Here is what you need before ordering and completing the Reverse T3 Test – rT3 Testing in ND. 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 ND. 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 North Dakota communities

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

Fargo207,310Reverse T3 Test – rT3 TestingBismarck89,825Reverse T3 Test – rT3 TestingGrand Forks63,767Reverse T3 Test – rT3 TestingMinot48,005Reverse T3 Test – rT3 TestingWest Fargo37,913Reverse T3 Test – rT3 TestingWilliston27,368Reverse T3 Test – rT3 TestingDickinson24,851Reverse T3 Test – rT3 TestingMandan23,784Reverse T3 Test – rT3 TestingJamestown15,823Reverse T3 Test – rT3 TestingWahpeton7,928Reverse T3 Test – rT3 TestingValley City6,586Reverse T3 Test – rT3 TestingWatford City5,725Reverse T3 Test – rT3 TestingMinot AFB5,375Reverse T3 Test – rT3 TestingGrafton4,186Reverse T3 Test – rT3 TestingLincoln4,126Reverse T3 Test – rT3 TestingHorace3,141Reverse T3 Test – rT3 TestingBeulah3,070Reverse T3 Test – rT3 TestingNew Town2,745Reverse T3 Test – rT3 TestingGrand Forks AFB2,678Reverse T3 Test – rT3 TestingHazen2,564Reverse T3 Test – rT3 TestingRugby2,546Reverse T3 Test – rT3 TestingCasselton2,493Reverse T3 Test – rT3 TestingBottineau2,141Reverse T3 Test – rT3 TestingCarrington2,133Reverse T3 Test – rT3 TestingLisbon2,109Reverse T3 Test – rT3 TestingStanley2,079Reverse T3 Test – rT3 TestingOakes1,981Reverse T3 Test – rT3 TestingMayville1,964Reverse T3 Test – rT3 TestingLangdon1,924Reverse T3 Test – rT3 TestingBelcourt1,751Reverse T3 Test – rT3 TestingHarvey1,701Reverse T3 Test – rT3 TestingHillsboro1,613Reverse T3 Test – rT3 TestingBowman1,604Reverse T3 Test – rT3 TestingGarrison1,577Reverse T3 Test – rT3 TestingPark River1,577Reverse T3 Test – rT3 TestingWashburn1,545Reverse T3 Test – rT3 TestingBurlington1,534Reverse T3 Test – rT3 TestingSurrey1,430Reverse T3 Test – rT3 TestingLarimore1,385Reverse T3 Test – rT3 TestingNew Rockford1,374Reverse T3 Test – rT3 TestingCavalier1,357Reverse T3 Test – rT3 TestingTioga1,335Reverse T3 Test – rT3 TestingParshall1,317Reverse T3 Test – rT3 TestingCando1,228Reverse T3 Test – rT3 TestingShell Valley1,227Reverse T3 Test – rT3 TestingThompson1,194Reverse T3 Test – rT3 TestingRolla1,192Reverse T3 Test – rT3 TestingMapleton1,169Reverse T3 Test – rT3 TestingFort Totten1,167Reverse T3 Test – rT3 TestingVelva1,120Reverse T3 Test – rT3 TestingHettinger1,116Reverse T3 Test – rT3 TestingCrosby1,076Reverse T3 Test – rT3 TestingEllendale1,067Reverse T3 Test – rT3 TestingEnderlin1,039Reverse T3 Test – rT3 TestingBeach1,017Reverse T3 Test – rT3 Testing