Content of prostaglandins E (PGE) as well as activity of glutathione-S-transferase (GST) were studied in T lymphocytes, neutrophils and blood plasma of patients with hashishism as compared with healthy volunteers. Decrease in content of PGE was found in the blood cells studied but not in blood plasma of these patients, while distinct decrease of PGE by 40% occurred only in neutrophils. However, activity of GST was considerably decreased both in the cell fractions and blood plasma by 79-81%. The narcotic appears to affect the immunity system by means of the prostaglandin E metabolism impairment, thus suggesting the prostaglandin study in various immunity-related cells of the patients with narcomania. Besides, glutathione-S-transferase activity proved not to be a deciding factor affecting the prostaglandin content in leukocytes and blood plasma.