Cortisol suppresses the immune system by preventing cytokine release, inhibiting antibody production, and
inhibiting the inflammatory response. Allergic reactions to bee stings, poison ivy, and pollen involve the immune
system; thus cortisol can be used to suppress these responses. Rejection of a transplanted organ is also an immune
response. Negative feedback from the exogenous hormone inhibits ACTH production, which can result in atrophy
of the adrenal cortex. Hypercortisolism can also result, with symptoms similar to diabetes mellitus, and extra fat
deposition leading to "moon face," and changes in mood and cognition.