Cyanokit is used in an emergency setting as an antidote to cyanide poisoning. The active ingredient of Cyanokit is hydroxocobalamina form of vitamin B-12. Cyanokit is injected into your vein. Cyanokit helps body cells to convert cyanide to a different, benign form that may be removed from your body through urination. Cyanokit may be given only by a professional healthcare provider in an emergency case.