From a laboratory medicine perspective, the Association for Clinical Biochemistry and Laboratory Medicine (ACB) and the Royal College of Pathologists (RCPath) advise that: HbA1c may be unreliable in the presence of haemolytic anaemia, haemoglobinopathies, or nutritional deficiencies affecting red cell biology and the direction of distortion may be high or low Clinicians should document any known haematological conditions when requesting HbA1c, so laboratory staff can flag potential inaccuracies Serum B12 testing should be considered in patients on long-term metformin who are symptomatic or have risk factors for deficiency, in line with MHRA and NICE advice Alternative tests fasting plasma glucose, OGTT, or interim use of fructosamine/glycated albumin should be considered when HbA1c reliability is in doubt The NHS website (nhs.uk) provides patient-facing information on the HbA1c test and factors that can affect its accuracy, which patients may find a useful starting point
Do They Need to Be Refrigerated
If there is clinical improvement and if a reticulocyte response is observed, the same amount may be given on alternate days for seven doses, then every 3 to 4 days for another 2 to 3 weeks
What are the common side effects of these injections
For these individuals, vitamin B12 injections are often the most effective way to restore healthy B12 levels because they bypass the digestive system entirely, delivering the vitamin directly into the bloodstream for maximum absorption (around 95% compared to 25-50% for oral supplements)
