The causes of hyperprolactinaemia may be considered, in a simplified fashion, as resulting from four basic disorders of the prolactin secretion mechanism:
ΓÇó Hypothalamic dopamine deficiency
ΓÇó Defective dopamine delivery
ΓÇó Lactotroph insensitivity to dopamine
ΓÇó Stimulation of lactotroph cells
In some patients, however, it is not possible to elucidate the cause of hyperprolactinaemia.