These extremely rare side effects include: Reactive thrombocytosis during the first week of use in megaloblastic anaemia Hypersensitivity reactions including: rash, itching, exanthema, antibodies to HYDR0XOCOBALAMIN-transcobalamin II Anaphylaxis Hypokalaemia Headache, paraesthesia, tremor Irregular heartbeat (arrhythmias secondary to hypokalaemia) Nausea Vomiting Diarrhoea Fever, chills, hot flushes, dizziness, malaise, pain and / or swelling at the injection site Acne Abnormal colouration of the urine (chromaturia) B12 injections work quickly
doi:10.1177/1756284820927306 43 Hildebrandt, W., Sauer, R., Bonaterra, G., Dugi, K
Athletic Performance and Recovery Enhances endurance, reduces muscle soreness, and improves post-exercise recovery
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