Antipsychotics (hyperprolactinaemia)

Question 1

Hyperprolactinemia is associated with the use of antipsychotics (and very occasionally antidepressants). Dopamine inhibits prolactin and so dopamine antagonists increase prolactin levels.

All antipsychotics cause measurable changes in prolactin but some do not increase levels beyond the normal range. The degree of prolactin elevation is dose related.

It is often asymptomatic but is associated with the following:-

Answer 1

Galactorrhoea and breast growth
Amenorrhoea
Gynaecomastia
Hypogondism
Sexual dysfunction

Question 2

Psychiatric patients with long standing hyperprolactinaemia have an increased risk of:-

Answer 2

Osteoporosis
Breast cancer (females only

Question 3

Antipsychotics known to cause significant hyperprolactinaemia include:-

Answer 3

All the typical antipsychotics
Risperidone
Amisulpride
Zotepine

Question 4

Drugs not usually associated with hyperprolactinaemia include:-

Answer 4

Clozapine
Aripiprazole
Quetiapine
Olanzapine
Ziprasidone

Question 5

Monitoring

Answer 5

All patients should have a their prolactin measured before antipsychotic therapy and then should be asked about symptoms at three months (and if symptoms present it should be measured again). In cases where there are no symptoms, annual testing is recommended.

Antipsychotics that increase prolactin should be avoided in the following (where possible):

Patients under 25 (before peak bone mass)
Patients with osteoporosis
Patients with a history of hormone dependent cancer

Question 6

Treatment

Answer 6

In symptomatic cases or where there is concern about long-term risk (the actual prolactin level is not really a big deal) the options are:

Switch to an alternative antipsychotic less prone to hyperprolactineamia
Alternatively, aripiprazole (at 3-6 mg/day) can be added in as this can lower prolactin levels (note that this is a small dose as the minimally effective daily dose is 10 mg).
The last option is to add a dopamine agonist such as amantadine or bromocriptine (but these have the potential to worsen psychosis).