Vitamin B6 Supplements and Peripheral Neuropathy

The Therapeutic Goods Administration (TGA) has released a safety update regarding the potential for vitamin B6 supplements to cause peripheral neuropathy. Peripheral neuropathy is a known side effect of vitamin B6 that typically presents with tingling, burning, or numbness in the hands or feet.

Vitamin B6 is an umbrella term that refers to pyridoxine, pyridoxamine, pyridoxal, and their phosphorylated derivatives. The recommended dietary intake for adults falls between 1.3mg and 1.5mg per day. While clinical deficiency is rare, supplements are commonly taken in the form of multivitamin preparations, vitamin B complexes, and fortified food and beverage products such as energy drinks.

There are case reports of peripheral neuropathy occurring in people taking less than 50mg of vitamin B6 a day and in people taking multiple products that contain vitamin B6. To address this issue, the TGA has updated the labelling requirements for vitamin B6. Previously, products had to carry a warning about peripheral neuropathy when the daily dose exceeded 50mg. A warning is now required for all products containing daily doses exceeding 10mg. The permitted daily dose of vitamin B6 in products has also been reduced (from 200mg to 100mg for adults). Manufacturers have until 1 March 2023 to comply with these changes.

The TGA advises healthcare professionals to consider vitamin B6 toxicity in patients with peripheral neuropathy symptoms. Prompt diagnosis is required as neuropathy may be progressive if the vitamin B6 exposure continues. Suspected adverse effects can be reported to the TGA.