Plasma prolactin and cortisol concentrations in epileptic patients during the night.

Plasma cortisol and prolactin concentrations were determined every four hours, from 8 PM to 8 AM, in 19 epileptic patients during EEG recording of sleep. Data were compared with those obtained from 12 healthy young male volunteers studied under similar conditions. Patients had normal cortisol rhythm, with peak levels at 4 AM or 8 AM and trough at midnight. A sleep-related increase in prolactin concentration was observed in all patients. The range of prolactin concentrations in the patients was also normal. Treatment with valproic acid (ten patients) and frequent abnormal EEG discharges (five patients) did not affect cortisol and prolactin secretion.