Prolactin is made by the pituitary gland. Its release is held in check mainly by dopamine from the hypothalamus, so anything that interferes with dopamine signalling, from certain medicines to a pituitary tumour pressing on the gland's stalk, can let prolactin rise.
In women it drives breast milk production. In men its everyday role is less clear, but it is part of the hormonal choreography around sex. When levels stay high for weeks or months, a condition called hyperprolactinaemia, it can interfere with desire and erections and sometimes with testosterone production.
Prolactin is checked with a simple blood test. Because orgasm pushes it up for about an hour, and because some high readings reflect an inactive form of the hormone, a raised result is a reason for a closer look rather than an instant diagnosis.31
What does prolactin do in men?
One of its clearest jobs in men is around orgasm. In a study of ten healthy couples, orgasm during sex produced a marked rise in prolactin in both men and women that was still elevated an hour later.3
The researchers suggested this surge may help dial down sexual desire after orgasm.3 It is often mentioned as one piece of the refractory period puzzle, though it is unlikely to be the whole story. A normal post-sex rise is nothing to worry about.
What are the symptoms of high prolactin in men?
Erectile dysfunction is the main symptom that brings high prolactin to light in men, usually together with reduced sexual desire, and sometimes with changes to orgasm or ejaculation.1
It is often assumed prolactin causes these problems by lowering testosterone, but testosterone is normal in many men with high prolactin, and the effect probably also runs through the brain's own chemistry.1 Because a proportion of cases come from pituitary tumours, persistent high prolactin always deserves a proper look.1
The symptoms overlap with far more common causes of erection trouble, such as stress, blood vessel disease and relationship strain, so there is no way to spot high prolactin from symptoms alone. A blood test is the only way to know. Our piece on how stress affects erections and libido covers the commoner culprits.
- Low desire (libido)
- Erectile dysfunction
- Changes to orgasm or ejaculation
What causes high prolactin?
The main causes are certain medicines and prolactin-secreting pituitary tumours, called prolactinomas, which are usually benign.2 In men being assessed for erection problems, marked high prolactin is rare.
Across more than 3,200 men with erectile dysfunction, only 0.76% had markedly raised prolactin and 0.4% had a pituitary adenoma.1 There is also a lab quirk: around 10% of high readings on standard tests are due to macroprolactin, a bulky form of the hormone that is largely inactive, and ruling it out needs specialist testing.1
How is high prolactin treated?
Dopamine-agonist medicine is the first-choice treatment for sexual problems caused by high prolactin, and some men also benefit from sexual counselling.1 If prolactin stays high, imaging of the pituitary is needed to look for a tumour.1
The Endocrine Society's guideline covers how to work out the cause, how to handle medicine-related cases and how to manage prolactinomas.2 If a prescribed medicine may be the culprit, do not stop it on your own; talk to the prescriber about alternatives. High prolactin has been described as a serious but reversible condition, which is exactly why it is worth finding.1 For the wider picture of desire, see does testosterone affect sex drive?
Common questions
Does ejaculation raise prolactin?
Yes. Orgasm, whether from sex or masturbation, triggers a clear prolactin rise that can last around an hour before settling.3 This is normal and short-lived, and it is one reason a blood test for prolactin should not be taken shortly after sex.
Should prolactin be checked for erectile dysfunction?
There is no firm consensus. It is uncommon, but because high prolactin is serious and reversible, some experts argue for measuring it routinely in men with erection problems.1 Ask your doctor whether it makes sense for you.
Does high prolactin lower testosterone?
It can, but not always. Many men with high prolactin have normal testosterone, which suggests prolactin also affects sexual function in other ways.1
Read more on this
Does testosterone affect sex drive? Separating myth from mechanism
How stress affects erections and libido
Sources
- Buvat J. Hyperprolactinemia and sexual function in men: a short review. Int J Impot Res. 2003;15(5):373-377. PubMed
- Melmed S, et al. Diagnosis and treatment of hyperprolactinemia: an Endocrine Society clinical practice guideline. J Clin Endocrinol Metab. 2011;96(2):273-288. PubMed
- Exton MS, et al. Coitus-induced orgasm stimulates prolactin secretion in healthy subjects. Psychoneuroendocrinology. 2001;26(3):287-294. PubMed
Not medical advice. Written by Eric Stephens from the research cited above; not reviewed by a doctor. If something worries you, see a GP.