PRL and neoplasm: If hypopituitarism is suspected, the entire anterior pituitary profile should be investigated (it is perhaps best to consider the hormonal deficiencies by both region of secretion and individual axes which is not within the scope of this review), including prolactin (high with some tumours, drug treatments and stress, while low in other instances), 9 am cortisol, thyroid‐stimulating hormone, free thyroxine, insulin‐like growth factor‐1, LH, FSH and repeat testosterone.