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Vitamin C

CPT: 82180
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  • Ascorbic Acid
  • C, Vitamin

Special Instructions

Order Vitamin C (With Dilution) [123253] if sending specimens from patients on high-dose vitamin C (eg, cancer therapy) in which results are expected to be significantly above the reference interval.

Expected Turnaround Time

3 - 5 days

Related Documents

Specimen Requirements


Serum, frozen and protected from light


1 mL

Minimum Volume

0.5 mL (Note: This volume does not allow for repeat testing.)


Red-top tube or gel-barrier tube; amber plastic transport tube with amber top. (If amber tubes are unavailable, cover standard transport tube completely, top and bottom, with aluminum foil. Identify specimen with patient name directly on the container and on the outside of the aluminum foil. Secure with tape.) For amber plastic transport tube and amber-top, order LabCorp N° 23598.


Draw in chilled tube. Separate serum from cells as soon as possible following collection. Keep specimen on ice. Transfer specimen to a plastic transport tube before freezing. Protect specimen from light. To avoid delays in turnaround time when requesting multiple tests on frozen samples, please submit separate frozen specimens for each test requested.

Storage Instructions

Freeze immediately and protect from light. Stable for five days at -30°C and one month at -70°C. There is a 61% decrease in levels in the first 24 hours following collection if the sample is allowed to remain at room temperature.

Patient Preparation

Overnight fasting is preferred. Refrain from taking vitamin C supplements or fruits 24 hours prior to sample collection.

Causes for Rejection

Specimen not received frozen; specimen not protected from light

Test Details


Evaluation of vitamin C deficiency


High-pressure liquid chromatography (HPLC) with electrochemical (EC) detection

Reference Interval

• 0 to 11 months: Not established

• 1 to 12 years: 0.2−2.3 mg/dL

• 13+ years: 0.2−2.0 mg/dL

Additional Information

Serum levels of vitamin C are an adequate measurement of clinical status. Vitamin C is a cofactor for protocollagen hydroxylase; it promotes the conversion of tropocollagen to collagen.1 Low values occur in scurvy, malabsorption, alcoholism, pregnancy, hyperthyroidism, and renal failure. Smokers have lower levels than nonsmokers. Patients with scurvy have values <0.2 mg/dL. Principal clinical findings in scurvy include bleeding gums, petechiae, follicular hyperkeratosis, perifollicular hemorrhages beginning on the lower thighs, muscle aches, easy fatiguability, and emotional changes.


1. McCormick DB. Vitamins. In: Tietz NW, ed. Fundamentals of Clinical Chemistry. 3rd ed. Philadelphia, Pa: WB Saunders Co;1987:497-516.


Order Code Order Code Name Order Loinc Result Code Result Code Name UofM Result LOINC
001479 Vitamin C 1903-4 001479 Vitamin C mg/dL 1903-4

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