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Switch to oral B12 urged

By Aruna Prabhala

GPs should consider prescribing oral vitamin B12 therapy instead of intramuscular injections in patients with B12 deficiency, new research suggests.

High doses of 2,000 or 1,000 µg daily were just as effective as intramuscular injections in achieving haematological and neurological responses, concluded a Cochrane review, published early online in Family Practice.

The researchers said more research was needed to assess long-term outcomes but advised GPs to trial oral therapy in newly diagnosed patients.

Study leader Dr Josep Vidal-Alaball, specialist registrar in public health medicine at the National Public Health Service for Wales, said: 'Although studies have suggested equal efficacy and safety of the oral route and a very safe track re-cord, vitamin B12 is rarely prescribed in the oral form in the UK.'

He added: 'Intramuscular injections are a considerable source of work for health care professionals. Oral treatment could save considerable NHS


In patients with newly diagnosed vitamin B12 deficiency who had an intact terminal ileum, he advised GPs to do an initial intramuscular injection followed by a trial of high-dose oral therapy.

Dr Chaand Nagpaul, a GP

in Edgware, Middlesex, and member of the GPC prescribing sub-committee, said he already offered oral vitamin B12 to his patients.

'I have noticed that some of my colleagues don't administer it to their patients. Perhaps some patients prefer an injection every three months rather than taking a pill every day,' he said.

Dr Elizabeth Nyholm, a GP in Birmingham who previously carried out research showing high levels of compliance with oral vitamin B12 in primary care, said patients should be offered the choice.

'Oral B12 in a dose of 1,000mµ a day is undoubtedly as effective as intramuscular injections of B12 (three-monthly at a dose of 1000µg) for patients with all causes of B12 deficiency including pernicious anaemia', she said.

Dr Nyholm said lack of availability of high-dose formulations in the UK was the

main reason for poor use of oral therapy.

The Cochrane team looked

at two randomised controlled trials of 108 patients.

Vitamin B12 levels were significantly higher in the oral group at two and four months compared with the intramuscular group.

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