Potassium Supplementation and B-12 Deficiency

Submitted by deb on Mon, 06/27/2011 – 04:50

Patients who take potassium chloride long-term, i.e., are at risk for developing vitamin B-12 deficiency. Potassium supplements such as K-Dur, Micro-K, Slow-K, K-Lyte, etc. interfere with the absorption of vitamin B-12 and can eventually lead to the depletion of body stores of this crucial vitamin. 1, 2, 3

Unlike other B vitamins, vitamin B-12 is stored in the body. Most people have enough B-12 stored in their liver and other organs to last from three to four years. But if the supply is interrupted long enough a deficiency can result, which can be devastating if not recognized and treated appropriately. Patients and their physicians should be aware that neurological symptoms of B-12 deficiency may begin well in advance of any laboratory evidence of disease. 4

Early symptoms of B-12 deficiency are often numbness and paresthesis (pins and needles sensation) in the hands and feet, weakness and ataxia (poor balance, staggering). There may be shortness of breath, loss of appetite, a sore mouth and tongue.

Neurological symptoms ranging from mild irritability, confusion and forgetfulness to suspicion and paranoia. Severe cases can exhibit severe dementia and frank psychosis. There may be sphincter disturbances (incontinence), Reflexes may be increased or decreased. The Romberg and Babinski signs may be positive and the patient may exhibit Lhermitte’s sign when the neck is flexed forward. It should be emphasized that neurologic disease may occur in a patient with normal hematocrit and normal CBC indexes.

Symptoms of anemia may include: weakness, light-headedness, vertigo, and tinnitus, as well as palpitations, angina, and the symptoms of congestive (heart) failure. The patient may be pale, with a rapid pulse. The heart may be enlarged. Loss of appetite with diarrhea and other gastrointestinal symptoms may be reported, along with moderate weight loss.4 It was felt that B-12 must be administered by injection, but oral B-12 supplements which dissolve under the tongue are now said to be adequate for replacement, if taken when there is no potassium in the stomach.


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2. Acta Med Scand. 1974 Dec;196(6):525-6. Drug-induced malabsorption of vitamin B12. VII.

3. Palva IP, Salokannel SJ, Palva HL, Rytkonen U, Timonen T. Malabsorption of B12 treatment with potassium citrate. PMID: 4456986

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5. Babior, BM and Bunn F, ‘Megaloblastic Anemias’ in “Harrison’s Principles of Internal Medicine”, Fauci AS., Braunwald E, Isselbacher K, Wilson J, Martin JB., Kasper DL., Hauser SL., Longo DL. ; eds. 14th Edition, Mc Graw-Hill, NYC; 1998, pp. 653 -659

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7. Hansten, PD., Horn JR, eds. “Drug Interactions and Updates”, Vancouver, Wash.; Applied Therapeutics, 1990.

8. Olin, BR., ed. “Drug Facts and Comparisons”. St. Louis; Facts and Comparisons 1991.

9. Roe, DA., ‘Diet, Nutrition and Drug Reactions’ in “Modern Nutrition in Health and Disease 7th Ed.”;

10. Shils, ME, Vernon RY, eds, Philadephia; Lea and Febiger, 1988 pp-630-645, Tatro, DS., ed. “Drug Interaction Facts”. St. Louis; Facts and Comparisons 1992.