Prolactin and galactorrhoea

Question 1

What is Prolactin secreted by?

Answer 1

Anterior pituitary gland

Question 2

What causes galactorrhea?

Answer 2

Action of Prolactin on breast tissue

Question 3

What is the primary Prolactin releasing inhibitor?

Answer 3

Dopamine
Thus dopamine agonists e.g. Bromocriptine can be used to control galactorrhea

Question 4

What are the features of excess prolactin in men and women?

Answer 4

M: impotence, loss of libido, galactorrhoea
F: amenorrhoea, galactorrhoea

Question 5

List 7 causes of raised prolactin

Answer 5

Prolactinoma
Pregnancy
Oestrogens
Physiological: stress, exercise, sleep
Acromegaly (1/3 of patients)
PCOS
Primary hypothyroidism

Question 6

How does primary hypothyroidism cause raised prolactin?

Answer 6

Thyrotrophin releasing hormone (TRH) stimulates prolactin release

Question 7

List 4 drug causes of raised prolactin

Answer 7

Metoclopramide, Domperidone
Phenothiazines
Haloperidol
Very rare: SSRIs, opioids