A proposed class action against Blackmores has revealed the potentially devastating effects of vitamin B6 toxicity — with growing concern around pregnant women unknowingly consuming dangerous levels.

More than 1,000 Australians have contacted lawyers about neurological symptoms they believe are linked to excessive B6 in over-the-counter supplements, many marketed as safe multivitamins or magnesium blends.

Among them is 33-year-old Dominic Noonan O’Keefe, a father from Victoria, who started taking supplements to prepare for the arrival of his baby daughter.

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“The main motivation was my daughter’s coming. I want to be as ready as possible for that period,” he said.

He says what followed was months of escalating, unexplained symptoms including nerve pain, loss of balance, visual issues and overwhelming fatigue.

"I remember standing at my desk and I had this electric shock of nerve pain shoot up in my scalp. Everything became overwhelming. I couldn’t deal with it. The light was too bright. The noises were too loud ... I thought I was having an aneurysm or something ... I thought I was dying"

Dominic continued to deteriorate over several months as specialists searched for answers, but routine tests failed to check his B6 levels. The turning point came not from the medical system, but a family barbecue.

“My whole family knew I was incredibly unwell ... I just said, ‘Oh, my arms are just so numb and they feel like they’re vibrating…’ and [my stepsister] stopped for a second, she’s like, ‘Are you taking any supplements?’ he said.

“She flipped me some peer-reviewed literature ... and immediately I knew what was going on.

“The next day I got a blood test and my results were double what they needed to be for peripheral neuropathy, which is just shorthand for nerve damage.”

Polaris principal lawyer Nick Mann is leading the proposed class action against Blackmores. He says the firm has now received more than 20 inquiries from women who were pregnant or breastfeeding while taking B6-containing supplements.

"You could be taking a pregnancy multivitamin and a magnesium supplement combined. You could have 50, 60 times the recommended daily intake of B6."

“To date, we’ve also received about 20 inquiries from women who were taking multivitamins while pregnant or breastfeeding. That’s something that we’re investigating.”

Mann believes this is just the beginning of what could be a much larger health issue, driven by regulatory gaps and marketing practices within the supplement industry.

“What we’ve since discovered is that there are thousands of Australians out there who are likely to have been affected by this,” Mann said.

While most people associate vitamin supplements with health benefits, B6 — also known as pyridoxine — can accumulate in the body over time, particularly if consumed through multiple sources.

“One of the things that I think the companies haven’t well understood or appreciated is that you could be taking a few different supplements at the same time ... you could be taking 50 times the recommended daily intake of B6,” he said.

“We are yet to see any convincing evidence that it needs to be in these supplement. You can go down to your local chemist and find an almost identical product which contains magnesium as the primary supplement sitting next to one that contains 30 to 40 times the recommended daily intake of B6.”

A spokesperson for Blackmores has told 7NEWS it’s committed to the “highest standards of product quality and consumer safety”.

“All our products, including those containing vitamin B6, are developed in strict accordance with the safety and regulatory requirements of the Therapeutic Goods Administration (TGA).

“This includes compliance with maximum permitted daily doses and the inclusion of mandated warning statements on product labels. We acknowledge the interim decision issued by the TGA and we will ensure full compliance with its final determination, prioritising the safety of our products.

“Vitamin B6 is in a range of products within the vitamins and dietary supplement industry and its inclusion in some Blackmores products is consistent with industry practice and meets current regulatory requirements in all markets.”

Dominic is one of the first to come forward and says he hopes speaking out will prompt real change.

“I feel embarrassed initially and a bit of shame like I think everyone does ... there’s a part of you that realises you were doing it, you were taking the supplements and unknowingly poisoning yourself,” he said.

“You can go into chemists still to this day and there won’t be warning labels. I didn’t have the luxury of that on any of my supplements. There are still supplements to this day in chemists without warnings on them.”

"This whole thing doesn’t seem right and I think we need to do something about it."

Mann says the proposed legal action is the first B6 class action of its kind globally. It’s gaining international attention and even prompting whistleblowers from inside the supplement industry to come forward.

"This is the first class action in the world that’s been brought in relation to B6 toxicity."

“We’re proud to bring it.

“What I can say so far is that from those inquiries, what we understand is that there was a huge reliance on what was approved by the TGA, but then no other consideration of safety and efficacy.

"The regulation of complementary medicines in Australia seems to have followed what’s called a light-touch regulatory approach."

Mann stresses that their legal case is not against the regulator, but against the companies with a duty of care to protect the public.

“The TGA regulation doesn’t and can’t be the beginning and the and of the legal liability ... You can’t, at law, say, well the regulator allowed us to do this and so therefore that’s our legal liability.”

Vitamin B6 is also added to food and drinks particularly breakfast cereals, protein bars and energy drinks.

Dr Terri-Lynne South from the Royal Australian College of General Practitioners says there needs to be better regulation in the food industry.

"There needs to be better regulation of those energy drinks because it is quite high. "

“There needs to be education and potentially some recommendations to pull them in line with what we’re seeing in those vitamin and mineral supplements.”

The TGA also responded to 7NEWS enquires: “The TGA has alerted consumers to the risk of neuropathy from vitamin B6, including a safety alert in 2022.

“Since March 2022, medicines providing over 10 mg equivalent vitamin B6 per day have required the label warning statement: ‘WARNING - Stop taking this medication if you experience tingling, burning or numbness and see your healthcare practitioner as soon as possible. [Contains vitamin B6].’

“In June, the TGA released an interim decision that proposes to change the current scheduling of vitamin B6 (pyridoxine, pyridoxal and pyridoxamine) such that oral preparations containing 50 mg or less per recommended daily dose are available for general retail sale (unscheduled).

“Oral preparations containing more than 50 mg but less than 200 mg per recommended daily dose would become Pharmacist only medicines (Schedule 3). This decision, if implemented, will reduce the maximum amount of vitamin B6 allowed in oral products than currently available for general sale.

“The interim decision balances the risks and benefits of using vitamin B6 including the risk of peripheral neuropathy, acknowledging its potential for irreversible harm at higher doses and variability in individual metabolism. It also considers the limited clinical need for supplementation due to dietary sufficiency, alongside the widespread use of vitamin B6 in fortified products and listed medicines.”

Dominic, now a year into recovery, still faces flare-ups triggered by illness or stress and lasting symptoms like numbness, vision problems, and fatigue.

“It feels like a heavy veil is over me and I’ve receded back into myself and I’m sort of just operating something that doesn’t a body that doesn’t work. But when I feel good, I feel present again,” he said.

“I feel me today.”

For him, the fight is about protecting others.

“I think it’s for the people that have been damaged ... The science has been pointing to this for decades. The companies need to do something to change it.”