You should also contact your GP if: You are unable to attend scheduled maintenance injections, as missing doses can lead to symptom recurrence You develop new symptoms that might indicate other deficiencies or health problems You are planning pregnancy, as B12 requirements may change You experience persistent side effects such as headaches, dizziness, or gastrointestinal symptoms If you experience any side effects, talk to your doctor, pharmacist or nurse
Frequency of injections: The frequency of vitamin B12 injections will depend on the severity of your deficiency and your doctor's recommendation
Cycle Length Most practitioners recommend cycles of 8-12 weeks, followed by a break
United Kingdom National Quality Assessment Scheme for Haematinic Assays (UK NEQAS), 18 February 2014
Unless specifically directed by a prescribing clinician, stick with bacteriostatic water for consistency and simplicity