In view of the demonstration by Jackson and others1 of the beneficial effects of pentose nucleotides in agranulocytic angina and other toxic leukopenias, the action of pentnucleotide in measles and in pertussis, both of which ordinarily exhibit quantitative or qualitative abnormalities in the leukocyte count, seemed worthy of investigation.
White cell counts were made every day and differential counts every other day in sixty-three cases of measles in thirty-three of which pentnucleotide was administered, and in twenty-four cases of pertussis, in ten of which the same treatment was given. Uncomplicated early cases were selected as far as possible. Studies were begun in the cases of measles on the third day of the rash, at the latest, and in the cases of pertussis within the first five days of definite whooping. It was originally planned to administer 10 cc. of the drug intramuscularly on five consecutive days. However, this dose