Hypothalamic-pituitary-adrenocortical hormones, i.e. prolactin (PRL), human growth hormone (hGH), thyroid stimulating hormone (TSH), and Cortisol and plasma levels of cytokines, i.e. tumor necrosis factor-alpha (TNF-alpha), interleukin 1 beta (IL-1 beta), and interleukin-6 (IL-6), were assessed in 27 patients with persistent vegetative state (PVS) and in 16 outcome patients. In comparison with normal parameters, plasma levels of TSH were not significantly altered, while elevated basal hGH concentrations in 48.1% of PVS subjects and depressed cortisol levels in all PVS individuals and in patients who emerged from coma (outcome patients), respectively, were observed. In addition, higher TNF-alpha plasma levels in PVS subjects than in outcome patients and in healthy donors were found, while IL-1 beta plasma levels were elevated in both groups of patients in comparison with healthy controls. Of interest, in 55% PVS male patients hyperprolactinemia was observed, whereas in outcome patients more than six months these values were within normal range. In four patients, who emerged from coma in the course of this study, prolactin plasma levels were followed-up and increased basal values progressively fell to normal range within six months.