Medication Summary
Pharmacotherapy involves the administration of vitamin B-12, folate, or both, as indicated. The goals of pharmacotherapy are to correct possible vitamin deficiencies, to prevent complications, and to reduce morbidity.
Vitamins
Class Summary
Cyanocobalamin (vitamin B-12) and folic acid are used to treat megaloblastic anemias secondary to cobalamin or folate deficiency. Both vitamin B-12 and folic acid are required for synthesis of DNA and some amino acids.
Cyanocobalamin (Calo-Mist, Ener-B, Nascobal)
Cyanocobalamin is most commonly given to patients. It is an in vitro artifact and is not an active form of the vitamin. However, it is converted to active forms.
Folic acid (Folvite)
Folic acid is an essential cofactor for enzymes used in DNA synthesis.
Electrolyte Supplements
Class Summary
Serum potassium levels can fall during therapy for severe cobalamin or folate deficiency and can lead to sudden death. Therefore, potassium supplements may be indicated.
Potassium chloride (K-Tab, Klor-Con, microK, Epiklor)
Potassium is essential for transmission of nerve impulses, contraction of cardiac muscle, maintenance of intracellular tonicity, skeletal and smooth muscles, and maintenance of normal renal function. Gradual potassium depletion occurs via renal excretion, through GI loss, or because of low intake.
Potassium depletion sufficient to cause 1 mEq/L drop in serum potassium requires a loss of about 100-200 mEq of potassium from body stores.
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