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

Pacific · Reverse T3 Test – rT3 Testing

Reverse T3 Test – rT3 Testing in Hawaii

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 Hawaii

Here is what you need before ordering and completing the Reverse T3 Test – rT3 Testing in HI. 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 HI. 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 Hawaii communities

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

Honolulu835,291Reverse T3 Test – rT3 TestingKailua106,260Reverse T3 Test – rT3 TestingEast Honolulu50,076Reverse T3 Test – rT3 TestingHilo46,559Reverse T3 Test – rT3 TestingPearl City45,941Reverse T3 Test – rT3 TestingWaipahu39,927Reverse T3 Test – rT3 TestingKaneohe34,509Reverse T3 Test – rT3 TestingEwa Gentry28,125Reverse T3 Test – rT3 TestingMililani Town27,974Reverse T3 Test – rT3 TestingKahului27,938Reverse T3 Test – rT3 TestingKapolei23,248Reverse T3 Test – rT3 TestingKihei22,840Reverse T3 Test – rT3 TestingMililani Mauka21,657Reverse T3 Test – rT3 TestingMakakilo20,862Reverse T3 Test – rT3 TestingSchofield Barracks18,255Reverse T3 Test – rT3 TestingWahiawa17,357Reverse T3 Test – rT3 TestingOcean Pointe16,676Reverse T3 Test – rT3 TestingWailuku15,670Reverse T3 Test – rT3 TestingHalawa14,990Reverse T3 Test – rT3 TestingEwa Beach14,614Reverse T3 Test – rT3 TestingRoyal Kunia14,390Reverse T3 Test – rT3 TestingWaianae14,152Reverse T3 Test – rT3 TestingWaimalu13,818Reverse T3 Test – rT3 TestingLahaina13,261Reverse T3 Test – rT3 TestingMaili13,245Reverse T3 Test – rT3 TestingNanakuli12,587Reverse T3 Test – rT3 TestingHawaiian Paradise Park11,942Reverse T3 Test – rT3 TestingKapaa11,516Reverse T3 Test – rT3 TestingWaihee-Waiehu11,059Reverse T3 Test – rT3 TestingWaipio10,989Reverse T3 Test – rT3 TestingWaimea10,422Reverse T3 Test – rT3 TestingHickam Housing10,022Reverse T3 Test – rT3 TestingMakaha9,710Reverse T3 Test – rT3 TestingAiea9,527Reverse T3 Test – rT3 TestingHaiku-Pauwela9,347Reverse T3 Test – rT3 TestingAhuimanu8,943Reverse T3 Test – rT3 TestingLihue8,371Reverse T3 Test – rT3 TestingMakawao7,670Reverse T3 Test – rT3 TestingWaikoloa Village7,519Reverse T3 Test – rT3 TestingKula7,495Reverse T3 Test – rT3 TestingWaikele7,495Reverse T3 Test – rT3 TestingPukalani7,315Reverse T3 Test – rT3 TestingKahaluu-Keauhou7,236Reverse T3 Test – rT3 TestingNapili-Honokowai6,762Reverse T3 Test – rT3 TestingEwa Villages6,657Reverse T3 Test – rT3 TestingWailua Homesteads6,634Reverse T3 Test – rT3 TestingWailea6,546Reverse T3 Test – rT3 TestingLaie6,436Reverse T3 Test – rT3 TestingWest Loch Estate6,239Reverse T3 Test – rT3 TestingIroquois Point5,737Reverse T3 Test – rT3 TestingWaipio Acres5,618Reverse T3 Test – rT3 TestingWaimanalo5,371Reverse T3 Test – rT3 TestingKahaluu5,006Reverse T3 Test – rT3 TestingHeeia4,777Reverse T3 Test – rT3 TestingKalaheo4,776Reverse T3 Test – rT3 TestingHaleiwa4,651Reverse T3 Test – rT3 TestingHanamaulu4,435Reverse T3 Test – rT3 TestingPupukea4,416Reverse T3 Test – rT3 TestingWaimanalo Beach4,389Reverse T3 Test – rT3 TestingHawaiian Beaches4,213Reverse T3 Test – rT3 Testing