The Weird Connection Between B12 Deficiency & Migraine Headaches Why Do I Feel Worse After My B12 Injection? Causes & Management Bolt Pharmacy B12 Injections for Energy: Benefits and How It Works AZ IV Medics A vitamin B12 deficiency can cause a range of symptoms, including some that appear in the mouth Vitamin B12 deficiency can cause symptoms like headaches, fatigue, depressive mood, gastrointestinal issues, and more. While vegetarians are at a higher risk of vitamin B12 deficiency, it can affect non vegetarians too. Check