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Covid-19 Primary Care Resources

How to convert to oral B12 for patients established on IM hydroxocobalamin

British Society for Haematology provide guidance on vitamin B12 replacement during the COVID-19 pandemic

This information is sourced from the British Society for Haematology (BSH):

Non-dietary vitamin B12 deficiency

Usual NICE 2019 recommendation: administer hydroxocobalamin 1 mg intramuscularly every 2-3 months for life

During the COVID 19 pandemic for patients established on intramuscular hydroxocobalamin:

  • As an alternative, oral cyanocobalamin can be offered at a dose of 1 mg per day until regular IM hydroxocobalamin can be resumed i.e. once GP surgeries are able to do so safely, aiming to have a shortest possible break from regular injections
  • Patients should be advised to monitor their symptoms and should contact their GP if they begin to experience neurological or neuropsychiatric symptoms such as pins and needles, numbness, problem with memory or concentration or irritability

Dietary Vitamin B12 deficiency

NICE Clinical Knowledge Summary 2019: advise people either to take oral cyanocobalamin tablets 50–150 micrograms daily between meals or have a twice-yearly hydroxocobalamin 1 mg injection

In vegans, treatment may need to be life-long, whereas in other people with dietary deficiency replacement treatment can be stopped once the vitamin B12 levels have been corrected and the diet has improved

During the COVID-19 pandemic for patients established on intramuscular hydroxocobalamin:

  • An alternative is to offer oral cyanocobalamin tablets, 50–150 micrograms, daily between meals
  • BSH recommend reassessing serum B12 prior to recommencing IM hydroxocobalamin
  • Many of these patients may be vitamin B12 replete with adequate levels within the liver, and therefore may be able to safely stop taking vitamin B12 supplements possibly for up to a year
  • Dietary advice should be given to all patients
  • Patients on vegetarian and especially vegan diets should continue taking oral supplements


Published: 01/05/2020