From the Guidelines
Vitamin B6 toxicity typically occurs from excessive supplementation rather than dietary sources, and symptoms primarily affect the nervous system, including painful, burning sensations in the hands and feet, numbness, tingling, muscle weakness, loss of balance, and difficulty walking, as reported in the most recent guideline 1. The symptoms of B6 toxicity can be severe and include:
- Peripheral neuropathy
- Numbness
- Tingling
- Muscle weakness
- Loss of balance
- Difficulty walking
- Skin lesions
- Photosensitivity
- Nausea
- Heartburn
- Headaches These symptoms usually develop gradually with long-term excessive intake, typically from supplements providing more than 100 mg daily over extended periods, as noted in the ESPGHAN guidelines 1. The recommended daily allowance for vitamin B6 is only 1.3-1.7 mg for adults, and toxicity rarely occurs below 50 mg daily, as stated in the ESPEN guidelines on definitions and terminology of clinical nutrition 1. If you're experiencing these symptoms and taking B6 supplements, discontinue use and consult a healthcare provider immediately for proper evaluation and management, as the condition is generally reversible when supplementation is stopped, though recovery can take months or even years in severe cases 1. Key points to consider:
- Excessive supplementation of B6 can produce painful neuropathy and skin lesions owing to axonal degeneration of sensory nerve fibres 1
- The optimal parenteral B6 dose for infants and children is not clear, but the ESPGHAN guidelines propose doses of 0.15-0.2 mg/kg/d for infants and of 1.0 mg/kg/d for children 1
- Micronutrient excess, including vitamin B6, can lead to specific symptoms, and clinical assessment and diagnosis play key roles in determining micronutrient excess 1
From the Research
Symptoms of B6 Toxicity
There are no research papers provided to directly answer the question about symptoms of B6 toxicity. The studies available are related to gabapentin, pregabalin, and their use in treating neuropathic pain, but they do not discuss B6 toxicity.
Related Information
- The studies provided compare the efficacy and safety of gabapentin and pregabalin in treating neuropathic pain 2, 3, 4, 5, 6.
- They discuss the mechanism of action of these drugs, their pharmacokinetic profiles, and their potential side effects 2, 3, 4, 5, 6.
- However, none of the studies mention B6 toxicity or its symptoms.
Key Findings
- Gabapentin and pregabalin are effective in treating neuropathic pain, but their comparative efficacy and safety are still being researched 2, 3, 4, 5, 6.
- The studies suggest that pregabalin may have a superior efficacy profile compared to gabapentin in some cases 6.
- Common side effects of these drugs include dizziness, somnolence, nausea, and vomiting 2, 3, 5, 6.