Prophylactic Use of Isoniazid

Abstract

The Commentary of Doctors Davis and Wedgwood on TB, PPT and INH presents up-to-date descriptions of some of the newer concepts of tuberculosis. Most of their conclusions concerning the implications of these new ideas to tuberculosis control are interesting and valid. I must, however, take issue with their statement that isoniazid has been shown to be safe and their implied recommendation of its use as a prophylactic measure against tuberculosis. May I call your attention to two investigations which are strongly suggestive that the prolonged use of isoniazid may lead to increased mortality.