Hi, I am new to this site and have found it very helpful. Three years ago after 3 weeks of blood tests I was diagnosed B12 deficiency and needed injections (initially 12 from then every 3 months). I am always very tired, concentration level low long before my due injection. I winter in South Africa and out there they give monthly injections, which I was told I needed and I felt absolutely great, on return I went for injection after two months as I was already feeling awful but was told I would have to have blood test, it came back at 240 and was told this is not low enough for earlier injections, I have to have one after 12 weeks before I can discuss more frequent injections. This test is due in two weeks time. In the meantime I feel exhausted. Can't wait to get back to South Africa 🇿🇦 they told me you cannot overdose as any excess is passed in the urine. Think I'll have a fight on my hands with my doctor, if I can get pass the Practice Nurse!