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Southwest · Magnesium RBC Test – Deficiency Testing

Magnesium RBC Test – Deficiency Testing in Arizona

Below is a plain-language overview of the magnesium rbc test – deficiency testing. A magnesium RBC test measures the amount of magnesium inside red blood cells, which some clinicians consider a more accurate reflection of body magnesium status than a serum magnesium test.

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

Lab requirements in Arizona

Here is what you need before ordering and completing the Magnesium RBC Test – Deficiency Testing in AZ. 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
Fasting is required for this test — follow the collection lab's instructions.
Preparation
Preparation instructions can vary, so follow the specific directions provided by the collection laboratory. This may include fasting or avoiding certain supplements before the test.
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. 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

This test evaluates the magnesium content within red blood cells rather than in the liquid portion of blood. Because most magnesium is stored inside cells, this test may provide a better picture of overall magnesium levels. It is sometimes used when a standard serum magnesium test is normal but a deficiency is still suspected.

What it measures

  • Magnesium (RBC) — Reflects the amount of magnesium stored inside red blood cells

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 this test to assess magnesium status when symptoms such as muscle cramps, weakness, or irregular heartbeat suggest a possible deficiency. It can also be used to monitor conditions or treatments that affect magnesium levels.

Preparation

Preparation instructions can vary, so follow the specific directions provided by the collection laboratory. This may include fasting or avoiding certain supplements before the test.

How results are reported

Results are typically reported as a number that is compared to a reference range established by the testing laboratory. Reference ranges can differ between laboratories, so your results should be interpreted in the context of the lab's own range.

Before you go

  • Whether fasting is required before the test
  • Any medications or supplements that might affect results
  • The specific reference range used by the testing laboratory

Cities

Magnesium RBC Test – Deficiency Testing in Arizona communities

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

Phoenix4,047,095Magnesium RBC Test – Deficiency TestingTucson875,284Magnesium RBC Test – Deficiency TestingMesa497,752Magnesium RBC Test – Deficiency TestingChandler272,439Magnesium RBC Test – Deficiency TestingGilbert262,249Magnesium RBC Test – Deficiency TestingAvondale254,537Magnesium RBC Test – Deficiency TestingGlendale245,685Magnesium RBC Test – Deficiency TestingScottsdale238,685Magnesium RBC Test – Deficiency TestingPeoria187,733Magnesium RBC Test – Deficiency TestingTempe178,862Magnesium RBC Test – Deficiency TestingSurprise141,875Magnesium RBC Test – Deficiency TestingYuma135,933Magnesium RBC Test – Deficiency TestingPrescott Valley97,901Magnesium RBC Test – Deficiency TestingSan Tan Valley96,127Magnesium RBC Test – Deficiency TestingGoodyear93,651Magnesium RBC Test – Deficiency TestingBuckeye89,711Magnesium RBC Test – Deficiency TestingFlagstaff81,682Magnesium RBC Test – Deficiency TestingCasas Adobes70,224Magnesium RBC Test – Deficiency TestingQueen Creek57,728Magnesium RBC Test – Deficiency TestingMaricopa57,075Magnesium RBC Test – Deficiency TestingLake Havasu City56,510Magnesium RBC Test – Deficiency TestingCasa Grande53,488Magnesium RBC Test – Deficiency TestingMarana50,834Magnesium RBC Test – Deficiency TestingCatalina Foothills50,096Magnesium RBC Test – Deficiency TestingOro Valley46,515Magnesium RBC Test – Deficiency TestingPrescott45,063Magnesium RBC Test – Deficiency TestingSierra Vista44,944Magnesium RBC Test – Deficiency TestingBullhead City41,064Magnesium RBC Test – Deficiency TestingApache Junction38,311Magnesium RBC Test – Deficiency TestingSun City37,693Magnesium RBC Test – Deficiency TestingEl Mirage35,410Magnesium RBC Test – Deficiency TestingSan Luis35,289Magnesium RBC Test – Deficiency TestingSahuarita33,524Magnesium RBC Test – Deficiency TestingKingman32,204Magnesium RBC Test – Deficiency TestingDrexel Heights30,599Magnesium RBC Test – Deficiency TestingFortuna Foothills26,727Magnesium RBC Test – Deficiency TestingSun City West26,354Magnesium RBC Test – Deficiency TestingFlorence25,356Magnesium RBC Test – Deficiency TestingFountain Hills23,639Magnesium RBC Test – Deficiency TestingAnthem22,750Magnesium RBC Test – Deficiency TestingRio Rico20,914Magnesium RBC Test – Deficiency TestingGreen Valley20,729Magnesium RBC Test – Deficiency TestingNogales19,829Magnesium RBC Test – Deficiency TestingNew River17,731Magnesium RBC Test – Deficiency TestingFlowing Wells16,965Magnesium RBC Test – Deficiency TestingDouglas16,470Magnesium RBC Test – Deficiency TestingPayson16,229Magnesium RBC Test – Deficiency TestingFort Mohave15,872Magnesium RBC Test – Deficiency TestingEloy15,171Magnesium RBC Test – Deficiency TestingTanque Verde14,946Magnesium RBC Test – Deficiency TestingSierra Vista Southeast14,822Magnesium RBC Test – Deficiency TestingVail14,715Magnesium RBC Test – Deficiency TestingSomerton14,126Magnesium RBC Test – Deficiency TestingSun Lakes13,912Magnesium RBC Test – Deficiency TestingCoolidge13,347Magnesium RBC Test – Deficiency TestingValencia West12,887Magnesium RBC Test – Deficiency TestingNew Kingman-Butler12,858Magnesium RBC Test – Deficiency TestingChino Valley12,854Magnesium RBC Test – Deficiency TestingParadise Valley12,666Magnesium RBC Test – Deficiency TestingVerde Village12,658Magnesium RBC Test – Deficiency Testing