b12 patches vs injections vs. Oral Supplements: Which Is Better? Vitamin B12 Injections vs. Supplements:

In Canada, advice from the British Columbia Medical Association outlines that 1 mg daily oral CN-Cbl should be used for pernicious anemia or food-bound cobalamin malabsorption (FBCM) whereas in most other cases, a daily dose of 250 g may be used ( In Netherlands, controversy arose when the Dutch Organization of General Practitioners published a 2014 viewpoint that 1 mg daily oral OH-Cbl can be utilised as treatment in cases with a cobalamin count below 148 pmol/L and clinical symptoms, with the Dutch B12 Society disputing the efficacy of this and insisting that the advice from the Dutch Healthcare Institute Pharmacotherapeutic Compass should be followed instead (IM/SC starting dose of 10 injections of 1 mg OH-Cbl at intervals of at least 3 days

[18] Thanks Warnings Dont rub the injection site

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But it could be helpful to screen people for B12 deficiency in advance and give them B12 supplements to delay or prevent the onset of depression