Hyperprolactinaemia increases intraocular pressure in humans.

Nine female and 2 male hyperprolactinaemic patients (plasma prolactin levels averaging 180-420 ng/ml) were subjected to measurements of intraocular pressure (IOP) either under basal conditions or after water load in comparison with 5 healthy volunteers. Basal values of IOP in hyperprolactinaemic patients were 37.8% higher than those of controls. Moreover, after water load hyperprolactinaemic patients showed a sustained increase in IOP that reached values of pathological significance. These results suggest that prolactin may contribute to the hormonal regulation of IOP in humans.