‘Ongoing risk’ as vitamin B6 warnings fail to dent sales

Mandatory warnings and public health alerts have made little difference to sales of supplements with vitamin B6, a University of Sydney study has found, with researchers saying their findings highlight ‘an ongoing risk’ of harm.
 
Using pharmacy sales data from 1 August 2022–31 July 2025 covering an estimated 75% of complementary medicine sales in Australia, they show more than 20 million products were sold which contained more than a daily dose of 5 mg.
 
The study, published in Internal Medicine Journal last month, also found more than three million products were sold with a daily dose higher than 50 mg of vitamin B6.
 
Such supplements will become pharmacist-only products from June 2027 under measures announced by the Therapeutic Goods Administration (TGA) last year, following a sharp rise in reports of neuropathy related adverse events linked to vitamin B6 products.
 
In March 2023, the TGA also introduced measures requiring products with daily doses of more than 10 mg to carry a safety warning, while the maximum allowable daily dose was reduced from 200 mg to 100 mg.
 
While researchers found ‘a marked decline’ in products with 200 mg or more following those changes, they said this was offset with more products delivering between 100 mg to 199 mg a day ‘suggesting substitution rather than a meaningful reduction in exposure’.
 
They said sales of vitamin B6 supplements ‘remained stable’ across the three years, concluding that mandatory warnings and a 2020 TGA safety alert on cumulative vitamin B6 exposure had no ‘discernible impact on purchasing patterns’.
 
They also warned ‘high-risk vitamin B6 purchasing behaviours are widespread in Australian community pharmacies’.
 
‘Given the dose- and duration-dependent relationship between pyridoxine and peripheral neuropathy and evidence of substantial interindividual variability in susceptibility, these findings highlight an ongoing risk of preventable neurotoxicity and under-recognised harm,’ they wrote.
 
Strengthened risk communication, improved consumer and health professional awareness, and more integrated pharmacist oversight is needed, researchers say, with regulatory reform alone ‘unlikely to adequately mitigate high-risk vitamin B6 use in Australia’.
 
Adjunct Associate Professor Jennifer Hunter, an academic GP at the University of Sydney and co-author of the paper, said an important finding is the extent to which people are buying different products which contain vitamin B6.
 
‘Even though the dose could be relatively low in each, if you’re taking multiple products you’ll quickly increase your dose – and the labelling on the products isn’t always that obvious,’ she told newsGP.
 
‘It really does highlight the importance for GPs to take a careful history whenever there might be some level of suspicion or alert to consider B6 toxicity. 
 
‘That might involve asking the patients to go home and carefully add up the total dose or bring in their bottles.
 
‘If you’re concerned about toxicity, particularly if symptoms aren’t 100% convincing, that might be when a B6 blood test could be indicated.’
 
Associate Professor Hunter also said that while millions purchases in Australia involve potentially high-risk products, ‘only a small proportion of people develop symptoms’.
 
‘The problem is we don’t really know what the risk is because we haven’t had any good epidemiological studies,’ she said.
 
She said she welcomes a conservative approach, with vitamin B6 supplements remaining on the market but high-dose products only being provided under medical supervision.
 
However, for Dr Mary Buchanan, a retired GP who has spoken publicly about the personal impact of vitamin B6 toxicity, the pace of change is not fast enough.
 
She said she is disappointed with ‘the very slow implementation’ of measures to reduce the availability of vitamin B6 products.
 
She noted at the end of October last year, the TGA had received 250 reports on the adverse events database of peripheral neuropathy linked with products containing vitamin B6, and that 152 reports of symptoms such as burning or paresthesia are ‘most likely to be neuropathy’. 
 
‘The TGA states there is no safe minimal dose, no safe duration of time, and that the neuropathy can be severe and irreversible,’ she told newsGP.
 
‘With the results of this study showing the alarming consumption of vitamin B6-containing products, the TGA must take more meaningful and effective methods to educate the general population, to review again the maximum B6 allowable in any product which is currently at 50 mg and to insist on very clear labelling on these products of potential side effects including muscle weakness.’
 
Currently, the tolerable upper limit for vitamin B6 in adults is set at 50 mg/day by the National Health and Medical Research Council, although a review is underway with results due in early 2027.
 
Dr Buchanan also believes pharmacists should ‘take responsibility’ and not stock or sell products with high amounts of B6.
 
A TGA spokesperson said the timing of the changes coming into effect next June ‘allow industry, healthcare practitioners and businesses sufficient time to implement, including updating product labelling and managing stock’.
 
‘The TGA will continue to educate people about this risk and the upcoming changes and provide advice to healthcare professionals,’ they told newsGP.
 
They said last year’s scheduling decision highlighted concerns around awareness of vitamin B6 content, cumulative exposure, and the efficacy of existing labelling requirements.
 
According to the spokesperson, a consultation paper will be released to ‘targeted stakeholder groups’ in the coming weeks including proposed extra measures to address those concerns.

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peripheral neuropathy TGA Therapeutic Goods Administration vitamin B6