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A Prophylactic and Therapeutic Trial

Thomas R. Karlowski, MD; Thomas C. Chalmers, MD; Lawrence D. Frenkel, MD; Albert Z. Kapikian, MD; Thomas L. Lewis, MD; John M. Lynch, MD

JAMA. 1975;231(10):1038-1042.

Abstract
Three hundred eleven employees of the National Institutes of Health volunteered to take 1 gm of ascorbic acid or lactose placebo in capsules three times a day for nine months. At the onset of a cold, the volunteers were given an additional 3 gm daily of either a placebo or ascorbic acid. One hundred ninety volunteers completed the study. Dropouts were defined as those who missed at least one month of drug ingestion. They represented 44% of the placebo group and 34% of those taking ascorbic acid. Analysis of these data showed that ascorbic acid had at best only a minor influence on the duration and severity of colds, and that the effects demonstrated might be explained equally well by a break in the double blind.

(JAMA 231:1038-1042, 1975)

Author Affiliations
From the Clinical Center (Drs. Karlowski, Chalmers, Frenkel, Lewis, and Lynch) and the National Institute of Allergy and Infectious Diseases (Dr. Kapikian), National Institutes of Health, Bethesda, Md. Dr. Chalmers is now with the Mount Sinai Medical Center and School of Medicine of the City University of New York, New York. Dr. Karlowski is now in private practice in Waterloo, Iowa. Dr. Frenkel is now in private practice in Washington, DC.

Footnotes
Reprint requests to Mount Sinai Medical Center, Fifth Ave and 100th St, New York, NY 10029 (Dr. Chalmers).

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