Is B12 making you break out? It's possible. We've found in our own experience and in clinical studies that certain forms of vitamin B12 can trigger inflammatory acne for some individuals. Taking Vitamin B12? Read this first. While B12 is often hailed as a safe energy and brain booster, many real users are reporting unexpected side effects including anxiety, insomnia, Breakouts from Vitamin B12 are some of the most common I see, even in longtime clients who are using excellent skin products and otherwise have their acne under control. , B12 causes inflamed acne and B12 injection & Acne Please don' Pernicious Anaemi