Sixty-two patients with ischemic stroke were studied over time (1st-12th day) for the activity of enzymes and isoenzymes of energy metabolism (CPK, LDH, SDH). It has been shown that the brain-specific CPK BB-isoenzyme may serve as a marker of the severity and extension of brain damage while the aerobic LDH fractions may be useful in evaluation of the reversibility of hypoxic changes in the brain. The authors consider the employment of the studied enzymes for the prognosis of vascular and tissue damage.