Vitamin B6 (pyridoxine)
Vitamin B6, also known as pyridoxine, is commonly present in multivitamin and mineral preparations, vitamin B complexes, and in combination with magnesium.
A known side effect of vitamin B6 is peripheral neuropathy, which has symptoms of tingling, burning or numbness, usually in the hands or feet. It usually occurs at high doses or following long-term use of products containing vitamin B6. Peripheral neuropathy is not associated with normal dietary intakes of vitamin B6.
Vitamin B6 is permitted for use in listed medicines containing daily doses of up to 200 mg.
There are currently more than 1000 listed medicines in Australia that contain vitamin B6. However, due to the risk of peripheral neuropathy, products that contain more than 50 mg are required to have the following warning displayed on the product label:
'WARNING - Stop taking this medication if you experience tingling, burning or numbness and see your healthcare practitioner as soon as possible. (Contains vitamin B6)'
Products containing 50 mg or less vitamin B6 are not currently required to display a label warning. This may make it difficult for consumers to identify reactions associated with vitamin B6, which could potentially lead to continued exposure and progression of neuropathy.
The TGA is aware of recent reports, both in Australia and overseas, which indicate that peripheral neuropathy may occur:
- at a daily dose of less than 50 mg a day of vitamin B6
- in consumers taking more than one product containing vitamin B6
The TGA is currently reviewing this issue and the outcome of this review may result in changes to the requirements for medicines that contain vitamin B6.
Information for consumers
You should be aware of the association between vitamin B6 and peripheral neuropathy, and that B6 may be in more than one of the products you take. Vitamin B6 might be listed on the label by one of its chemical names (pyridoxine hydrochloride, pyridoxal 5-phosphate or pyridoxal 5-phosphate monohydrate).
If you take products that contain vitamin B6, be aware of symptoms of peripheral neuropathy, such as tingling, burning, or numbness. If you experience any of these symptoms, you should stop taking the product and seek medical advice.
You should discuss any concerns or questions you have about this issue with your health professional.
Information for health professionals
You should be aware that peripheral neuropathy can occur at doses of less than 50 mg of vitamin B6 a day. Additionally, patients presenting with symptoms of peripheral neuropathy should be reviewed for vitamin B6 intake from sources such as B vitamins, multivitamins and/or magnesium products, particularly if taken in combination. When treating patients for peripheral neuropathy, you should consider whether a complementary medicine or dietary supplement could be involved.
Further information about the risks of vitamin B6 associated peripheral neuropathy was published in the August 2008 Australian Adverse Drug Reactions Bulletin.
Information for sponsors
During the TGA investigation of this issue, we identified a number of products that did not display the required label warning. Regulatory action has been taken to ensure available products are compliant.
You are reminded of your obligations to comply with the requirements of the permissible ingredients determination. Failure to do so will lead to regulatory action, which may include the recall and/or cancellation of a product.
You are also reminded of your obligation to report all serious adverse events to the TGA within required timeframes.
Consumers and health professionals are encouraged to report problems with medicines or vaccines. Your report will contribute to the TGA's monitoring of these products.
The TGA cannot give advice about an individual's medical condition. You are strongly encouraged to talk with a health professional if you are concerned about a possible adverse event associated with a medicine or vaccine.