Cyanocobalamine

Cyanocobalamin is a synthetic compound of vitamin B12 used to treat vitamin deficiencies. Chemically, cyanocobalamin is classified as a "corrinoid," representing a crystallizable cobalt complex. The name "cyanocobalamin" is derived from including a cyanide group within the molecule. Vitamin B12 facilitates several methylation reactions within the body. Methylcobalamin serves as a cofactor in the conversion of homocysteine to methionine in the body. Furthermore, in the form of adenosylcobalamin, the vitamin is crucial in converting methylmalonyl-coenzyme A (CoA) to succinyl-CoA. Both of these reactions are essential for cell division and growth.

Cyanocobalamin is approved by the United States Food and Drug Administration (FDA) for pernicious anemia, malabsorption, atrophic gastritis, gastrectomy, Helicobacter pylori infection, and other conditions.

Cyanocobalamine can cause a variety of adverse drug reactions, including allergic reactions such as itching, erythema, and clammy skin. Its dermal adverse drug reactions include acne, rosacea, and allergic reactions to cyanocobalamin injections. Other common adverse reactions include: shortness of breath (even with mild exertion), swelling, rapid weight gain; pulmonary oedema, congestive heart failure, peripheral vascular thrombosis; hypokalaemia (leg cramps, arrhythmia, tingling/numbness, muscle weakness, or claudication sensation); numbness or tingling and joint pain; fever; swelling of the tongue; itchiness or rash; and erythrocytosis.