Rapid Rx Quiz: Vitamin B12

Mary L. Windle, PharmD


October 31, 2022

Significant pain is the common adverse effect of intramuscular vitamin B12 therapy, especially in patients who are thin. Those who are taking anticoagulants may also experience bleeding from injectable cobalamin. Allergic reactions are rare but potentially life-threatening. Other common adverse effects from intramuscular vitamin B12 therapy include congestive heart failure, fever, hypokalemia, itching or rash, polycythemia, pulmonary edema, rapid weight gain, shortness of breath, tingling or numbness of joint, and vascular thrombosis. Glossitis and vitiligo are recognized clinical manifestations of a vitamin B12 deficiency.

Take a quick quiz on vitamin B nutritional disorders.


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