Any drugs which reduce dopamine will reduce inhibition of prolactin so increase prolactin levels
Dopamine antagonists e.g. metoclopramide
Antipsychotics e.g. phenothiazines
Less commonly: antidepressants e.g. TCA, SSRIs, oestrogens, cocaine
Pathological
Hypothyroidism
Stalk compression due to pituitary adenomas and other pituitary masses
Damage to stalk - iatrogenic, road accident
Prolactinoma
Clinical features
Patients may present with features of hyperprolactinaemia or structual symptoms from a pituitary tumour with headaches and visual loss (latter presentation more common in males)