---
title: "What does a low Vitamin B6 mean?"
type: biomarker-interpretation
url: "https://www.test-well.com/biomarkers/vitamin-b6/low"
biomarker: Vitamin B6
direction: low
reference_range:
  - "age 18+: 20.0 – 125 nmol/L"
reviewed_at: 2026-09-06
review_status: reviewed
date_published: 2026-09-05
---

# What does a low Vitamin B6 mean?

> Low vitamin B6 occurs with alcohol use, kidney disease, malabsorption, autoimmune and inflammatory conditions, and several medications — isoniazid, hydralazine, some anticonvulsants, oral contraceptives. It contributes to anemia, dermatitis, mood symptoms and raised homocysteine. Diet alone rarely causes it in the US except with very restricted eating.


## What is the normal range for Vitamin B6?

- age 18+: 20.0 – 125 nmol/L

Can reflect alcohol use, certain medications, or absorption issues.

## What are the common causes of low Vitamin B6?

1. Alcohol use disorder
2. Medications: isoniazid, hydralazine, penicillamine, levodopa-carbidopa, some anticonvulsants, oral contraceptives
3. Malabsorption, celiac disease, kidney disease on dialysis
4. Chronic inflammation and autoimmune disease
5. Restricted diets, older age

## What symptoms go with low Vitamin B6?

- Fatigue, irritability, low mood
- Cracks at the corners of the mouth, scaly rash, sore tongue
- Tingling, confusion in severe deficiency

## What do clinicians usually check next?

- CBC (microcytic anemia can result), homocysteine
- Medication and alcohol review
- Retest 8–12 weeks after correcting the cause

Follow-up tests at TestWell: [CBC with Differential](https://www.test-well.com/tests/cbc-with-differential) ($21.99), [CBC (Complete Blood Count)](https://www.test-well.com/tests/cbc) ($21.99), [Homocysteine](https://www.test-well.com/tests/homocysteine) ($27.99).

## How do you recheck Vitamin B6?

| Test or panel | Type | Price | Fasting | Results |
| --- | --- | --- | --- | --- |
| [Vitamin B6 (Pyridoxine)](https://www.test-well.com/tests/vitamin-b6-pyridoxine) | Test | $51.99 | No | 3–5 business days |

Plus one $6 lab processing fee per order; physician authorization included.

## Common questions

### Should I supplement if my B6 is low?

Correcting a documented deficiency is reasonable at modest doses; the trap is high-dose long-term use, which causes neuropathy. A clinician sets the dose and duration.

## Related

- [What does a high Vitamin B6 mean?](https://www.test-well.com/biomarkers/vitamin-b6/high)
- [Vitamin B6 reference ranges](https://www.test-well.com/biomarkers/vitamin-b6)
- [Vitamin D, 25-Hydroxy reference range](https://www.test-well.com/biomarkers/vitamin-d-25-hydroxy)
- [Vitamin B12 reference range](https://www.test-well.com/biomarkers/vitamin-b12)
- [Folate reference range](https://www.test-well.com/biomarkers/folate)

## Sources

- [Mayo Clinic Labs](https://www.mayocliniclabs.com/test-catalog/overview/42360)

---

Medically reviewed by Youmna DiStefano, MD (Medical Reviewer, TestWell); last reviewed 2026-09-06. Review policy: https://www.test-well.com/editorial-policy

Canonical page: https://www.test-well.com/biomarkers/vitamin-b6/low
Machine-readable catalog: https://www.test-well.com/api/catalog.json · MCP server: https://www.test-well.com/mcp · Overview for agents: https://www.test-well.com/llms.txt

Prices are cash-pay, in USD, and include physician authorization; every order adds one flat $6 lab processing fee. Educational content is not a diagnosis — discuss results with a clinician.