What happens if you take excess vitamin B6? Understanding the risks of too much pyridoxine

October 13, 2025 •

4 min read

According to reports submitted to the Therapeutic Goods Administration (TGA), many people are unaware that vitamin B6 is present in numerous health supplements and can cause adverse side effects like peripheral neuropathy. This highlights the importance of understanding what happens if you take excess vitamin B6, especially from supplements, and the dangers of overconsumption.

Quick Summary

Overconsumption of supplemental vitamin B6, also known as pyridoxine toxicity, can lead to nerve damage called peripheral neuropathy. Symptoms include numbness, tingling, and poor coordination, which may be severe or even permanent in some cases. Unlike dietary sources, high-dose supplements are the cause of toxicity, making careful reading of product labels crucial.

Key Points

Peripheral Neuropathy: Prolonged high-dose vitamin B6 supplementation can cause nerve damage, leading to numbness, tingling, and burning sensations in the hands and feet.
Ataxia and Coordination Issues: Excess vitamin B6 can result in a lack of muscle control and poor coordination, causing an unsteady gait and difficulty walking.
Toxicity from Supplements, Not Food: Vitamin B6 toxicity is almost exclusively caused by high-dose supplements, as intake from dietary sources is considered safe.
Safe Upper Limit Exists: Health authorities, like the TGA, have set the daily tolerable upper intake level for adults at 100 mg, recognizing that adverse effects can occur below this limit in some people.
Recovery Is Possible But Slow: For most, symptoms improve after discontinuing supplementation, but recovery can take months or years, and nerve damage can sometimes be permanent.
Check All Product Labels: Vitamin B6 can be a hidden ingredient in multivitamins and other supplements, so it is essential to check labels for pyridoxine and its chemical names to avoid accidental overconsumption.

What is Vitamin B6 and Why Is It Essential?

Vitamin B6, or pyridoxine, is a water-soluble vitamin that plays a vital role in over 100 enzyme reactions in the body. It is critical for many bodily functions, including metabolism, nerve function, and red blood cell formation. Your body needs vitamin B6 to produce neurotransmitters, support immune function, and help maintain normal blood sugar levels.

Unlike fat-soluble vitamins, water-soluble vitamins like B6 are not stored in the body for long and any excess is typically excreted through urine. However, when consumed in extremely high doses from supplements over an extended period, it can build up in the nervous system and lead to toxicity.

Excellent dietary sources of vitamin B6 include chickpeas, beef liver, fish like tuna and salmon, potatoes, and bananas. Consuming vitamin B6 through food is generally considered safe and will not cause toxicity, even in larger amounts.

The Dangers of Excessive Vitamin B6 from Supplements

Vitamin B6 toxicity, also called pyridoxine toxicity, is almost exclusively caused by the long-term use of high-dose supplements, not from food sources. The primary concern with this toxicity is its effect on the nervous system, leading to a condition known as peripheral neuropathy. This involves damage to the peripheral nerves—those outside the brain and spinal cord—resulting in a range of sensory and motor symptoms.

Symptoms of Excess Vitamin B6

The most common symptoms of B6 toxicity are neurological in nature, but other effects may also occur.

Peripheral Neuropathy: Numbness, tingling, or a burning sensation, typically in the hands and feet. This is often described as a 'stocking-glove' pattern.
Ataxia: A loss of muscle control and coordination, leading to an unsteady gait or difficulty walking.
Photosensitivity: An increased sensitivity to sunlight.
Dermatological Lesions: Painful or disfiguring skin lesions in some cases.
Gastrointestinal Issues: Heartburn, nausea, and stomach pain have been reported.
Sensory Changes: A reduced ability to sense pain or distinguish between extreme temperatures.
Mood Disturbances: Irritability and fatigue can also occur.

Safe Intake vs. Dangerous Excess

Understanding the distinction between safe recommended daily intake (RDI) and the tolerable upper intake level (UL) is crucial for preventing toxicity.


Feature	Recommended Daily Allowance (RDA)	Tolerable Upper Intake Level (UL)	Toxic Intake	Potential Outcomes
Adults (19-50 years)	1.3 mg/day	Up to 100 mg/day (some regions have lower limits)	Typically >100 mg/day for extended periods; can occur at lower doses in some individuals	Necessary for normal bodily functions; deficiency is rare but possible	Safe for most healthy adults; intake from food sources is not toxic	Risk of peripheral neuropathy, pain, and numbness; potential for irreversible damage	Source:	Dietary foods (meat, fish, vegetables)	Supplements, fortified foods	High-dose supplements

Some authorities, like the Australian TGA, have lowered the maximum permitted daily dose in supplements to 100 mg for adults and require a warning for any product containing more than 10 mg. This reflects growing evidence that peripheral neuropathy can occur at daily doses significantly lower than previously thought and that risk varies between individuals.

Navigating Supplementation Safely

Many people take supplements without realizing the potential for overconsumption, especially when taking multiple products. It is important to be aware that some supplements, particularly those containing magnesium or B-complex vitamins, also contain B6 and can contribute to excessive daily intake.

To ensure you are not overdoing it, read all labels carefully and consider the total daily intake of vitamin B6 from all supplements combined. If you are taking high doses for a specific condition, it is vital to do so under a doctor's supervision.

Diagnosis and Treatment

Diagnosing vitamin B6 toxicity involves a thorough medical history, including all supplements and dosages, and a physical neurological examination. A doctor may also perform nerve conduction velocity studies or blood tests, though blood levels do not always correlate perfectly with symptom severity. The primary treatment is to immediately stop taking the B6 supplement.

Symptoms may improve over several months after discontinuation, but recovery can be slow, and in some severe cases, the nerve damage may be permanent. Supportive care, including pain management and physical therapy, may be necessary to address persistent symptoms.

Conclusion

While vitamin B6 is a crucial nutrient for many aspects of health, the consequences of excessive intake from high-dose supplements can be severe and long-lasting, with peripheral neuropathy being the most serious risk. Given that it is abundant in a wide variety of foods, most healthy individuals do not need to supplement with B6. For those who do take supplements, staying well within the tolerable upper intake level (UL) and monitoring for symptoms of toxicity is crucial. Always consult a healthcare professional before starting any new supplement regimen, especially if you plan to take high doses over an extended period. Staying informed and cautious is the best way to avoid the serious health risks associated with too much vitamin B6.

Frequently Asked Questions

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

No, it is highly unlikely to develop vitamin B6 toxicity from food sources alone. Toxicity is virtually always associated with prolonged, high-dose supplementation.

While the tolerable upper intake level (UL) for adults is 100 mg per day, evidence shows that toxicity can occur at lower doses, especially with long-term use. Doses exceeding 50 mg for an extended period have been linked to neuropathy in some individuals.

Early signs often include sensory changes such as numbness, tingling, or a burning sensation in the extremities. An unsteady gait or difficulty with coordination may also indicate a problem.

The main treatment for vitamin B6 toxicity is to stop all supplementation containing B6 immediately. Recovery can be slow, but symptoms often gradually improve over time. In some cases, supportive care like physical therapy may be needed.

Recovery time varies depending on the severity of the toxicity and how long high doses were taken. For some, symptoms resolve within months, while others may experience lingering or permanent nerve damage.

Most side effects from vitamin B6 toxicity are reversible once supplementation is stopped. However, nerve damage can be permanent in some severe cases, highlighting the importance of early detection and intervention.