Vitamin B1 (Thiamine), Plasma
Ordering Recommendation
Do not use to determine thiamine deficiency.
Quantitative High Performance Liquid Chromatography
2-4 days  
New York DOH Approval Status
This test is New York DOH approved.
Submit With Order
Specimen Required
Patient Preparation
Green (sodium or lithium heparin), lavender (EDTA), plasma separator tube, or pink (K2 EDTA).  
Specimen Preparation
Separate plasma from cells within one hour of collection. Protect from light within one hour of collection, and during storage and transport. Transfer 3 mL plasma to an ARUP Amber Transport Tube. (Min: 0.2 mL)  
Storage/Transport Temperature
Frozen. Separate specimens must be submitted when multiple tests are ordered.  
Unacceptable Conditions
Hemolyzed specimens or specimens other than heparin or EDTA plasma.  
After separation from cells: Ambient: Unacceptable; Refrigerated: 1 week; Frozen at -20°C: 6 months  
Reference Interval
8-30 nmol/L  
Interpretive Data
Total thiamine, measured as thiamine (vitamin B1) and thiamine monophosphate, is reported. However, thiamine diphosphate (TDP), the biologically active form of the vitamin, is best measured in whole blood and is not found in measurable concentration in plasma. Plasma thiamine concentration reflects recent intake rather than body stores.

See Compliance Statement B:
Statement B: This test was developed and its performance characteristics determined by ARUP Laboratories. The U.S. Food and Drug Administration has not approved or cleared this test; however, FDA clearance or approval is not currently required for clinical use. The results are not intended to be used as the sole means for clinical diagnosis or patient management decisions.
Whole blood is the preferred specimen for thiamine assessment. Approximately 80 percent of thiamine present in whole blood is found in red blood cells. Refer to Vitamin B1 (Thiamine), Whole Blood (0080388).
CPT Code(s)
Component Test Code*Component Chart NameLOINC
0080389Vitamin B1, Plasma2999-1
* Component test codes cannot be used to order tests. The information provided here is not sufficient for interface builds; for a complete test mix, please click the sidebar link to access the Interface Map.
  • B1 Vitamin
  • Thiamine
  • Thiamine monophosphate
  • Vitamin B1 (Thiamine),
  • VITB1