The most consistently documented side effect of excessive B12 is dermatological reactions, particularly acne-like eruptions and rosacea flare-ups
Still, side effects from B12 supplements are possible, especially at higher doses, and include: Headache Nausea Vomiting Fatigue Weakness Diarrhea Tingling in the hands and feet Nasal spray Vitamin B12 is also available in a nasal spray
(Provides pharmacological details on pyridoxine, including its role as a coenzyme in neurotransmitter synthesis and interactions such as the antagonism of levodopa and reduction of phenytoin levels)
Vitamin B12 Medicine Interactions Chloramphenicol: bacteriostatic antibiotic can interfere with red blood cell response to supplemental Vit B12 Proton pump inhibitors: omeprazole and lansoprazole, etc., slow gastric acid release and may interfere with VIt B12 absorption from food H2-receptor antagonists: cimetidine, famotidine and ranitidine slow the release of hydrochloric acid into the stomach and interfere with Vitamin B12 absorption from food Metformin: might reduce absorption of Vitamin B12 due to altered intestinal motility, increased bacterial overgrowth, etc
Lipotropic injections include a combination of the following important amino acids and vitamins