Adaptive reactions were studied in 80 patients with acute pneumonia. I
n the hospital 94.1 % patients showed reactions of stress and incomple
te reactions of training and activation. With improvement of the clini
cal condition the number of stress reactions reduces, while the number
of physiological reactions of training and activation increased. The
stress reaction is an unfavourable factor as to transition ef acute pn
eumonia into chronic unspecific pulmonary diseases. These studies may
be of value for evaluation of the prognosis and care of acute pneumoni
a.