What can too much vitamin B6 do to your body?

November 17, 2025 •

4 min read

According to the NIH, an adult's safe upper limit for vitamin B6 intake is 100 mg per day, though toxicity has been reported at lower levels. Taking too much vitamin B6, almost exclusively from supplements rather than food, can lead to serious health problems, including permanent nerve damage.

Quick Summary

Taking excessive vitamin B6 supplements can lead to a condition known as peripheral neuropathy, causing tingling, numbness, pain, and loss of coordination, typically in the hands and feet. This nerve damage is a key consequence of long-term high-dose B6 intake.

Key Points

Nerve damage is the primary risk: Excessive intake of supplemental vitamin B6 can cause peripheral neuropathy, a type of nerve damage that results in numbness, tingling, and pain in the hands and feet.
Supplements are the main culprit: Toxicity is almost exclusively linked to chronic high-dose vitamin B6 supplementation, not from consuming foods naturally rich in the vitamin.
Neurological symptoms are most common: Key symptoms of toxicity include peripheral neuropathy, ataxia (loss of coordination), and impaired sensation.
Recovery can be slow or incomplete: Treatment involves stopping all B6 supplements, but nerve damage recovery can take months or years, and in some cases, can be permanent.
Be cautious with combination supplements: Many multi-vitamins and other combined supplements contain vitamin B6, so it is important to check total daily intake from all sources.
Mimics deficiency symptoms: B6 toxicity can present with symptoms similar to a B6 deficiency, a paradox that can make diagnosis difficult.

The dangers of excessive vitamin B6 supplements

While vitamin B6 is a crucial nutrient for a wide range of bodily functions, including metabolism and neurotransmitter production, excessive intake is linked to a serious and potentially irreversible condition. The primary risk associated with consuming too much vitamin B6, usually in the form of supplements containing pyridoxine, is damage to the nervous system, which is known as peripheral neuropathy.

Unlike most water-soluble vitamins that the body easily excretes, high levels of B6 can accumulate and cause damage to the peripheral nerves, which are located outside the brain and spinal cord. The most common symptoms affect the body's extremities, causing significant discomfort and issues with physical coordination. Natural food sources of B6, such as fish, poultry, potatoes, and non-citrus fruits, do not cause toxicity, and issues are almost always the result of over-supplementation.

Symptoms of vitamin B6 toxicity

The symptoms of vitamin B6 toxicity often develop gradually over time with chronic high-dose intake. The effects can be debilitating and significantly impact a person's quality of life. The severity of symptoms can vary, and some individuals may be more susceptible to the toxic effects than others.

Peripheral Neuropathy: A tingling, burning, or numb sensation in the hands and feet is the most common symptom, often described as a 'stocking-glove' sensation.
Ataxia: This refers to a loss of muscle control and coordination, leading to difficulty walking, unsteady gait, and issues with balance.
Photosensitivity: An increased sensitivity to sunlight can lead to painful skin lesions and disfigurement.
Dermatological Issues: In addition to skin sensitivity, individuals may develop painful or unsightly skin patches.
Gastrointestinal Problems: Nausea and heartburn are also reported symptoms.
Reduced Sensation: Some people may experience a decreased ability to feel pain or sense extreme temperatures.

Diagnosis and treatment for B6 toxicity

If vitamin B6 toxicity is suspected, it is crucial to consult a healthcare professional. A diagnosis is typically made by evaluating the patient's medical history, including all dietary supplements taken, and performing a thorough neurological exam. Blood tests may also be conducted to measure vitamin B6 levels, though these may not always correlate with symptom severity.

The primary and most essential step for treatment is to stop taking all vitamin B6 supplements immediately. Unfortunately, there is no specific antidote for B6 toxicity. Recovery from nerve damage can be a slow process, sometimes taking months or even years. While symptoms often improve after discontinuing supplementation, in severe or prolonged cases, the nerve damage can be permanent.

For ongoing symptoms, supportive care and management may be necessary, and may include:

Pain medication to help alleviate neuropathic pain.
Physical therapy to improve muscle strength and coordination.
Occupational therapy to help individuals adapt to any lasting limitations.

Why supplement forms are dangerous

One of the main reasons for toxicity is the form of B6 commonly used in supplements, primarily pyridoxine. Research suggests that high levels of this inactive form can competitively inhibit the active form of the vitamin, pyridoxal-5-phosphate, disrupting normal nerve function. This contrasts with the vitamin B6 from food sources, which the body can regulate more effectively.

Comparison: B6 deficiency vs. toxicity

It is a known medical paradox that the symptoms of B6 toxicity can sometimes mimic those of a deficiency, which can complicate diagnosis. The table below clarifies the distinction.


Feature	Vitamin B6 Deficiency	Vitamin B6 Toxicity
Cause	Insufficient dietary intake, poor absorption, or certain medications	Chronic, high-dose supplementation (rarely from food)
Neurological Symptoms	Depression, confusion, and in infants, seizures or irritability	Peripheral neuropathy, causing numbness, tingling, pain, and loss of coordination
Dermatological Symptoms	Seborrheic dermatitis, scaly lips, and cracks at the corners of the mouth	Painful, disfiguring skin lesions due to photosensitivity
Other Symptoms	Anemia, weakened immune system	Ataxia, heartburn, nausea, reduced sensation
Risk Factors	Kidney disease, autoimmune disorders, alcohol dependence	Long-term use of high-dose supplements

Conclusion

While vitamin B6 is essential for health, the potential consequences of over-supplementation cannot be ignored. The condition of peripheral neuropathy, caused by taking too much vitamin B6, can lead to chronic and, in some cases, permanent nerve damage. Awareness is key, and individuals taking supplements—especially combination products that can inadvertently lead to high doses—must be vigilant about their intake. The adult Tolerable Upper Intake Level (UL) is set at 100 mg per day, but risks can occur even below this level. Always check supplement labels for all forms of B6 and consult a healthcare provider with any concerns or before starting high-dose supplementation. Early identification and cessation are the most effective management strategies for mitigating the risks associated with an excessive intake of this crucial vitamin.

For more detailed information on vitamin B6 safety, consult the NIH Office of Dietary Supplements.

Frequently Asked Questions

The primary danger of taking too much vitamin B6 is the risk of developing peripheral neuropathy, a type of nerve damage that causes symptoms like numbness, tingling, and pain, especially in the hands and feet.

No, it is highly unlikely to get too much vitamin B6 from food alone. Vitamin B6 toxicity almost always results from taking high-dose dietary supplements over an extended period.

The Tolerable Upper Intake Level (UL) for adults is 100 mg per day. However, some health authorities recommend a lower limit, and toxicity can occur below this level in some individuals.

The main treatment for B6 toxicity is to stop taking any supplements containing the vitamin immediately. There is no specific antidote, and management focuses on supporting the body as it slowly eliminates the excess B6.

Recovery time varies depending on the severity and duration of the overdose. While some people see symptoms improve after stopping supplements, it can take months or years, and some nerve damage may be irreversible.

Yes, other symptoms can include a loss of muscle control (ataxia), painful skin lesions due to increased sun sensitivity (photosensitivity), nausea, and heartburn.

The common supplemental form, pyridoxine, can interfere with the body's use of the active form of B6, pyridoxal-5-phosphate. This disruption can cause neurological symptoms that paradoxically resemble a deficiency.