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At the moment Methylcobalamin is proven to be very effective as a B12 supplement either as an injection or sublingual tablets

Measurement of serum methylmalonic acid should be used to confirm deficiency in asymptomatic high-risk patients with low-normal levels of vitamin B 12

Medicare mandates that B12 injections must be administered by a qualified healthcare professional in an approved outpatient facility to qualify for coverage

Standard laboratory protocols are summarized below researchers should validate against their own internal SOPs

Connor et al., 1996

Others find that nausea compounds tamoxifen's GI side effects and requires slower titration or dose reduction