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Vitamin B1 (Thiamine),Blood, LC/MS/MS
Quest Diagnostics1 test optionFrom $80.68
Vitamin B1 (Thiamine),Blood, LC/MS/MS
Quest DiagnosticsCatalog information reviewed: August 24, 2026 by the Sunridge Medical clinical team.
What this laboratory test evaluates
Vitamin B1 (Thiamine), Blood, LC/MS/MS
This test measures the level of Vitamin B1 in the blood, which is crucial for breaking down amino acids and carbohydrates. It's especially important for people who might not be getting enough Vitamin B1, often due to alcoholism or chronic illnesses. Early signs of Vitamin B1 deficiency include loss of appetite, irritability, lack of interest, and general weakness. If not addressed, it can lead to beriberi, a serious condition.
Who might need this test?This test is particularly useful for individuals showing symptoms of Vitamin B1 deficiency or those at risk due to lifestyle or chronic conditions.
Symptoms of Vitamin B1 Deficiency:• Loss of appetite
• Irritability and apathy
• General weakness
• Prolonged deficiency can lead to beriberi
What type of sample is required for this test?2 mL whole blood collected in an EDTA (lavender-top) tube – protected from light.
Test Resources:For more information, consult your healthcare provider.
Additional test information
Vitamin B1 is required for branched-chain amino acid and carbohydrate metabolism. Vitamin B1 deficiency is most often due to alcoholism or chronic illness. In the early stage, patients with vitamin B1 deficiency exhibit anorexia, irritability, apathy, and generalized weakness. Prolonged deficiency causes beriberi.
Collection and processing
- Sample type: Whole blood
- Fasting: Yes
- Estimated laboratory processing: Results should be available in 2 – 5 business days after the sample is collected
How Sunridge uses laboratory information
Sunridge considers the medical question, symptoms, history, medications, prior results, and whether the finding could change care before recommending testing. A laboratory result is not interpreted in isolation and does not establish a diagnosis by itself.
Before requesting this test
Availability, collection requirements, eligibility, and processing estimates can change. Sunridge reviews each request and, when appropriate, creates the order through Fullscript. Follow the current instructions supplied with the approved order.
Common questions about this laboratory test
- What sample does this test require?
- The listed sample type is Whole blood. Confirm current collection instructions in the approved order.
- Does this test require fasting?
- The current catalog record lists fasting as: Yes. Follow the instructions supplied with the approved order.
- How long does laboratory processing usually take?
- Results should be available in 2 – 5 business days after the sample is collected. Timing can change after collection or if a laboratory requires additional review.
About this test
Vitamin B1 (Thiamine), Blood, LC/MS/MS
This test measures the level of Vitamin B1 in the blood, which is crucial for breaking down amino acids and carbohydrates. It's especially important for people who might not be getting enough Vitamin B1, often due to alcoholism or chronic illnesses. Early signs of Vitamin B1 deficiency include loss of appetite, irritability, lack of interest, and general weakness. If not addressed, it can lead to beriberi, a serious condition.
Who might need this test?This test is particularly useful for individuals showing symptoms of Vitamin B1 deficiency or those at risk due to lifestyle or chronic conditions.
Symptoms of Vitamin B1 Deficiency:• Loss of appetite
• Irritability and apathy
• General weakness
• Prolonged deficiency can lead to beriberi
What type of sample is required for this test?2 mL whole blood collected in an EDTA (lavender-top) tube - protected from light.
Test Resources:For more information, consult your healthcare provider.
Additional details
Vitamin B1 is required for branched-chain amino acid and carbohydrate metabolism. Vitamin B1 deficiency is most often due to alcoholism or chronic illness. In the early stage, patients with vitamin B1 deficiency exhibit anorexia, irritability, apathy, and generalized weakness. Prolonged deficiency causes beriberi.
Highlighted health areas
- Metabolic function
- Nutrition
Biomarkers and report focus
The exact analytes and report format can change. Confirm the current contents in the Fullscript order before payment.
- Vitamin B1 (Thiamine), Blood