Prolactin blood test: what high and low prolactin levels mean
Prolactin (PRL) · Hormone panel (ordered alone or with TSH, LH, FSH, estradiol or testosterone) · reported in ng/mL (equivalent to mcg/L). Some labs report mIU/L: 1 ng/mL ≈ 21.2 mIU/L
Prolactin is the pituitary hormone that prepares the breasts for milk production and sustains it after birth. Outside pregnancy and breastfeeding it circulates at low levels in everyone, and a prolactin blood test measures how much. Normal is below about 25 ng/mL in non-pregnant women and below about 15 to 20 ng/mL in men, depending on the lab; in late pregnancy it rises to 200 ng/mL or more. Too much prolactin (hyperprolactinemia) is the commonest pituitary hormone abnormality and shuts down the reproductive axis, which is why the test is ordered for missed periods, infertility, unexpected milk production, low testosterone and erectile dysfunction.
The two most common reasons for a high result are medications and the stress of the blood test itself. Antipsychotics (risperidone in particular), the anti-nausea drugs metoclopramide and domperidone, some antidepressants, opioids and oral estrogen all raise prolactin, often to 50 to 100 ng/mL and sometimes above 200. A difficult venepuncture, a sleepless night, exercise or sex that morning can nudge a normal value to 30 or 40. An underactive thyroid, chronic kidney disease and, rarely, a seizure or chest-wall injury are the other everyday causes.
The reason the test matters is the prolactinoma, a benign pituitary tumour that makes prolactin and is the most common pituitary tumour, affecting roughly 1 in 1,000 to 2,000 people. Levels above 200 to 250 ng/mL almost always mean one, and the number roughly tracks its size. Two laboratory traps complicate interpretation: macroprolactin, a harmless antibody-bound form that inflates the result in 10 to 25 percent of 'high' samples, and the hook effect, in which an enormous tumour saturates the assay and reads falsely low. Both are solved by asking the lab, not by more worry.
PRL at a glance
- What it is: the pituitary hormone that drives milk production; held in check by dopamine from the hypothalamus, so anything that blocks dopamine raises it.
- Normal: women (non-pregnant) under about 25 ng/mL; men under about 15–20 ng/mL; pregnancy 30–400 ng/mL by the third trimester. Labs differ; 1 ng/mL ≈ 21 mIU/L.
- Mildly high (25–100 ng/mL): medications, stress of the draw, hypothyroidism, kidney disease, PCOS, a non-functioning pituitary tumour pressing on the stalk, macroprolactin or a small prolactinoma.
- Markedly high (above 200–250 ng/mL): nearly always a prolactinoma; levels over 1,000 suggest a large one (macroadenoma). Some antipsychotics can reach 200.
- Low prolactin (under about 3–5 ng/mL): rarely important; seen with dopamine-agonist drugs, pituitary failure and some medications; may impair breastfeeding.
- Next step: repeat on a calm, rested morning without a breast exam, sex or exercise beforehand, ask the lab to check for macroprolactin, review medicines, check TSH and kidney function, and have a pituitary MRI if the level is confirmed above about 100 or unexplained.
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What PRL measures
Prolactin is made by lactotroph cells in the front of the pituitary gland. Unlike most pituitary hormones it is mainly held off rather than switched on: dopamine travelling down the pituitary stalk from the hypothalamus continuously suppresses it. Anything that blocks dopamine receptors (antipsychotics, metoclopramide), depletes dopamine, or physically interrupts the stalk (a tumour, surgery, trauma) releases the brake and prolactin rises. Estrogen, thyrotropin-releasing hormone (which rises in hypothyroidism), suckling, stress, sleep, exercise, orgasm and seizures stimulate it directly. High prolactin in turn suppresses GnRH, so LH, FSH, estradiol and testosterone fall, which is how it causes missed periods, low libido and infertility.
Labs measure prolactin by immunoassay. The hormone exists in three sizes: the active 23 kDa monomer (usually 80 to 90 percent), a 'big' dimer, and 'big-big' prolactin or macroprolactin, which is monomeric prolactin stuck to an IgG antibody. Macroprolactin is biologically inert and cleared slowly, so it builds up and is counted by most assays as if it were active hormone. It explains 10 to 25 percent of raised results, and people with it have none of the usual symptoms. Labs screen for it by precipitating the sample with polyethylene glycol (PEG) and re-measuring; a recovery of monomeric prolactin under about 40 percent means macroprolactinemia. Many labs do this automatically for any result over a threshold; if yours does not, ask.
The hook effect is the opposite trap. In a two-site immunoassay, an extremely high prolactin (typically above 10,000 ng/mL from a giant macroadenoma) saturates both antibodies so that fewer sandwiches form and the result reads deceptively modest, perhaps 30 to 100 ng/mL. Whenever a large pituitary mass is seen on imaging with only a mildly raised prolactin, the lab should re-run the sample at a 1:100 dilution. Prolactin also has a daily rhythm, highest during sleep and in the first hours after waking, so a sample drawn later in the morning, two to three hours after waking, when rested and unstressed, is the standard.
Normal range for PRL
Reference ranges vary between labs and by age, sex and pregnancy. Use the range printed on your own report.
| Group | Typical range (ng/mL (equivalent to mcg/L). Some labs report mIU/L: 1 ng/mL ≈ 21.2 mIU/L) | Notes |
|---|---|---|
| Women, non-pregnant | About 4–25 ng/mL (roughly 85–530 mIU/L) | Upper limits range from 20 to 29 ng/mL between labs; use the printed cut-off. |
| Men | About 3–15 ng/mL; many labs allow up to 18–20 | Slightly lower than in women because estrogen stimulates lactotrophs. |
| Pregnancy | First trimester up to about 100; third trimester 100–400 ng/mL | Rises steadily; falls to normal within a few weeks after birth if not breastfeeding. |
| Breastfeeding | Often 50–300 ng/mL in the early weeks; falls toward 20–50 by 6 months | Rises sharply during and after each feed. |
| Mild elevation | 25–100 ng/mL | Medications, stress, hypothyroidism, kidney disease, PCOS, macroprolactin, stalk compression by a non-functioning tumour, or a microprolactinoma. |
| Moderate elevation | 100–250 ng/mL | Most often a microprolactinoma (under 1 cm); some antipsychotics (risperidone, paliperidone, amisulpride) and metoclopramide can reach this range. |
| Marked elevation | Above 250 ng/mL | Almost always a prolactinoma; levels over 1,000 ng/mL indicate a macroadenoma (over 1 cm). Endocrine Society: a single value above 250 is sufficient for diagnosis once drugs are excluded. |
| Macroprolactin screen | Monomeric prolactin recovery under 40 percent after PEG precipitation | Indicates macroprolactinemia; the monomeric (active) prolactin is then reported separately and is usually normal. |
| Low prolactin | Below about 3–5 ng/mL | Seen with dopamine agonists, pituitary failure and some drugs; rarely clinically significant outside breastfeeding. |
High prolactin (hyperprolactinemia)
A high prolactin means the pituitary's lactotroph cells have escaped dopamine's control or are being stimulated, and the first step is to decide whether it is real. A value under about 50 ng/mL in someone who felt stressed by the draw, had exercised, had sex or a breast examination that morning, or slept badly should be repeated on a quiet morning two or more hours after waking; the Endocrine Society accepts a single measurement if it was taken without undue venepuncture stress but suggests repeating, or taking two to three samples through an indwelling cannula 15 to 20 minutes apart, when there is doubt. The lab should also exclude macroprolactin, which accounts for up to a quarter of raised values and needs no treatment.
Once confirmed, the level and the drug list usually point to the cause. Medications are the commonest explanation for a genuine elevation and typically give 25 to 100 ng/mL, though risperidone, paliperidone, amisulpride and metoclopramide can exceed 200. If it is safe, the drug is stopped for three days (with the prescriber's agreement) and the test repeated; if it cannot be stopped and the level is high, a pituitary MRI is still needed to exclude a tumour. Hypothyroidism (TSH), kidney disease (creatinine) and pregnancy (a pregnancy test in any woman who could be) are checked at the same time. Values above 200 to 250 ng/mL with no drug cause are a prolactinoma until proven otherwise, and the level correlates with tumour size.
A mild elevation (usually under 100 to 150 ng/mL) with a large pituitary mass on MRI is not a prolactinoma but 'stalk effect': a non-functioning tumour or other lesion pressing on the stalk and blocking dopamine delivery. The distinction matters because a prolactinoma shrinks with dopamine-agonist tablets whereas a non-functioning tumour needs surgery; the lab's diluted re-run (to rule out the hook effect) decides. High prolactin does its damage by suppressing GnRH: women develop irregular or absent periods, infertility and low estrogen with bone loss; men develop low testosterone, erectile dysfunction, infertility and sometimes breast enlargement. Treating the prolactin restores ovulation in 80 to 90 percent of women.
Common causes
Stress of venepuncture, exercise, sex, breast stimulation or poor sleep
Each can raise prolactin transiently to 30 to 50 ng/mL. This is why guidelines suggest a rested morning sample and a repeat, or cannulated serial samples, before diagnosing a mild elevation.
Antipsychotics and other dopamine-blocking drugs
Risperidone, paliperidone, amisulpride, haloperidol and phenothiazines raise prolactin in most people taking them, commonly to 50 to 100 ng/mL and sometimes above 200; aripiprazole, quetiapine and clozapine have little effect. Metoclopramide and domperidone act the same way.
Antidepressants, opioids, verapamil, estrogen and other medications
SSRIs and tricyclics raise prolactin modestly in a minority (usually under 50); opioids, methadone, verapamil, methyldopa, cimetidine (intravenous) and high-dose oral estrogen also raise it. Cocaine and some herbal products (fenugreek, fennel) can contribute.
Prolactinoma
The most common functioning pituitary tumour; microadenomas (under 1 cm) usually give 100 to 250 ng/mL and macroadenomas over 250, often in the thousands. Ten times more common in women, in whom periods stop; in men they are often found late, when large, because of headache or visual loss.
Hypothyroidism
Low thyroid hormone raises TRH, which stimulates lactotrophs; prolactin is usually 25 to 60 ng/mL and normalises with thyroid replacement. TSH should be checked with every raised prolactin.
Macroprolactin
Antibody-bound prolactin that is inactive but measured by the assay; explains 10 to 25 percent of raised results, typically 25 to 100 ng/mL, in people with no symptoms. Identified by PEG precipitation; needs no treatment or imaging.
Pituitary stalk compression by other tumours or lesions
Non-functioning adenomas, craniopharyngiomas, cysts, infiltrative disease (sarcoidosis, histiocytosis), surgery or trauma interrupt dopamine delivery; prolactin is mildly raised (usually under 100 to 150) despite a large mass.
Chronic kidney disease and cirrhosis
Reduced clearance and altered dopamine regulation raise prolactin to 25 to 100 ng/mL in a third or more of people on dialysis; cirrhosis has a smaller effect.
Pregnancy, breastfeeding and nipple stimulation
Physiological; prolactin reaches 200 to 400 ng/mL at term and stays raised while breastfeeding. A pregnancy test is part of the work-up in any woman who could be pregnant.
Polycystic ovary syndrome, seizures and chest-wall injury
A mild elevation occurs in some women with PCOS; a generalised seizure raises prolactin for 1 to 2 hours (sometimes used to distinguish it from a non-epileptic attack); shingles, burns or surgery on the chest wall stimulate the same nerve pathway as suckling.
Symptoms that can go with it
- Irregular, infrequent or absent periods, and difficulty conceiving, in women
- Milky discharge from the nipples not related to childbirth (galactorrhea), in women and occasionally men
- Low sex drive, vaginal dryness and painful sex in women; erectile dysfunction, low libido and reduced body hair in men
- Infertility and a low sperm count in men
- Breast enlargement in men (gynecomastia)
- Headaches, and loss of the outer edges of vision (bitemporal hemianopia) with a large tumour
- Bone thinning and fractures with long-standing untreated high prolactin
- Acne and excess hair growth in some women, from the associated hormonal shift
Low prolactin
Prolactin has no agreed lower limit of concern and a low value is rarely investigated in its own right. In most people a result of 1 to 4 ng/mL simply reflects the lower end of normal, a sample drawn late in the day when the hormone is at its trough, or a medication. The dopamine-agonist drugs cabergoline and bromocriptine, used for prolactinomas and Parkinson's disease, deliberately suppress it, sometimes to undetectable levels, and levodopa and some ergot derivatives do the same.
Low prolactin becomes meaningful in two settings. In a woman who has just given birth, a low level with difficulty producing milk can indicate pituitary damage, classically Sheehan's syndrome after a large postpartum haemorrhage, in which other pituitary hormones (cortisol, thyroid, LH and FSH) also fall; the inability to breastfeed is often the first clue. In anyone with a known pituitary tumour, surgery or radiation, a low prolactin is one piece of evidence for broader pituitary failure (hypopituitarism). Observational studies have linked low-normal prolactin with metabolic syndrome, diabetes and cardiovascular events, but the evidence is associative and does not justify testing or treatment.
Common causes
Dopamine agonists and dopamine-related drugs
Cabergoline, bromocriptine, quinagolide and levodopa suppress prolactin directly; a low or undetectable level in someone treated for a prolactinoma is the intended result.
Hypopituitarism
Pituitary tumours, surgery, radiation, head injury, infiltrative disease and Sheehan's syndrome reduce all front-pituitary hormones; low prolactin accompanies low cortisol, thyroid hormone, LH, FSH and growth hormone.
Sheehan's syndrome
Pituitary infarction after severe blood loss at delivery; failure to lactate followed by absent periods, fatigue and low blood pressure is the classic sequence.
Time of day and sampling
Prolactin peaks during sleep and falls through the day; an afternoon sample in a rested person can be 30 to 50 percent lower than a morning one.
Very low body weight and some medications
Prolonged energy deficit lowers prolactin along with LH and FSH; glucocorticoids, thyroid hormone excess and some anticonvulsants reduce it modestly.
Congenital isolated prolactin deficiency
Extremely rare; presents only as inability to breastfeed.
Symptoms that can go with it
- None in most people; a low prolactin does not cause symptoms outside the postpartum period
- Little or no breast milk after childbirth
- With pituitary failure: fatigue, weight loss, low blood pressure, absent periods or low libido, cold intolerance and low blood sugar
Read it alongside
- TSH and free T4 — hypothyroidism raises prolactin via TRH and is a correctable cause; checked with every raised result.
- Pregnancy test (hCG) — pregnancy is the commonest physiological cause of a high prolactin in a woman of reproductive age and must be excluded before imaging.
- LH, FSH and estradiol — high prolactin suppresses these; low or inappropriately normal LH and FSH with low estradiol confirm the reproductive axis is switched off.
- Testosterone — in men, high prolactin produces low testosterone with a low or normal LH; both usually recover when prolactin is treated.
- Creatinine and eGFR — chronic kidney disease reduces prolactin clearance and raises levels in a third or more of people with advanced disease.
- Macroprolactin (PEG precipitation) — the lab test that separates active monomeric prolactin from inert antibody-bound prolactin; ask for it with any unexplained mild elevation.
- IGF-1 — screens for growth hormone co-secretion in a confirmed prolactinoma and for acromegaly when features are present.
- Cortisol and other pituitary hormones — assessed when a large mass is seen on MRI, since a macroadenoma can compress normal pituitary tissue and cause deficiencies.
What usually happens next
- A mildly raised result (under about 50 to 100 ng/mL) is repeated on a calm morning two or more hours after waking, fasting or not, with no breast examination, sex, exercise or nipple stimulation beforehand, and a note of every medication and supplement you take.
- Ask whether the lab screened for macroprolactin; if not, request it, since up to a quarter of raised values are explained by it and need no further tests.
- Expect a TSH, creatinine, a pregnancy test where relevant, and LH, FSH with estradiol or testosterone; a review of medicines with your prescriber, including a supervised three-day pause if it is safe, is the next step when a drug is the likely cause.
- A confirmed level above about 100 ng/mL, any unexplained elevation, or any level with headaches or visual symptoms leads to a pituitary MRI with contrast; a large mass with only a mild elevation prompts the lab to re-run the sample diluted to exclude the hook effect.
- If a prolactinoma is found, ask about visual field testing for a macroadenoma, a bone density scan if periods have been absent or testosterone low for long, and the plan for monitoring (prolactin at 1 month after treatment starts, then every 3 to 12 months, with MRI as advised).
- Women planning pregnancy should ask how the diagnosis affects fertility treatment and what happens to medication once pregnant, since prolactinomas are managed differently in pregnancy.
Diet, lifestyle and natural levers with evidence
What can move PRL once the cause is known. Nothing here replaces finding the cause.
Test-day preparation: rest, no breast stimulation, no exercise or sex beforehand
Moderate evidenceVenepuncture stress alone raises prolactin by 10 to 50 percent in a meaningful minority of people, and the Endocrine Society notes that a value taken without undue stress is more reliable than a random one; studies of cannulated serial sampling in women with mild elevations found that 20 to 30 percent normalised on later draws. Avoiding exercise, sexual activity, nipple or breast examination and heavy meals for several hours, and sampling two or more hours after waking, removes the commonest causes of a false mild elevation.
Chasteberry (Vitex agnus-castus)
Preliminary evidenceVitex extracts act on pituitary dopamine D2 receptors. In a 3-month randomised trial of 52 women with mildly raised prolactin and a short luteal phase, 20 mg a day of extract reduced prolactin release in response to TRH and lengthened the luteal phase compared with placebo, and small trials in premenstrual syndrome and cyclic breast pain show modest prolactin reductions (roughly 10 to 30 percent from baseline levels that were already near normal). There are no trials in people with prolactin over 50 ng/mL or with prolactinomas.
Do not combine with dopamine agonists (cabergoline, bromocriptine) or antipsychotics, which act on the same receptors; avoid in pregnancy, breastfeeding and hormone-sensitive cancers; not a substitute for investigation when prolactin is clearly raised.
Vitamin B6 (pyridoxine)
Preliminary evidencePyridoxine is a cofactor for dopamine synthesis, and small studies from the 1970s and 1980s reported that 200 to 600 mg a day lowered prolactin in some people with mild elevations and in people on dialysis. Later controlled studies found little or no effect at ordinary doses, and the evidence does not support it as a treatment.
Doses above 100 to 200 mg a day for months can cause nerve damage (numbness, unsteadiness) that is not always reversible; do not use high doses without medical supervision.
Weight loss in women with PCOS or obesity
Preliminary evidenceProlactin is mildly raised in some women with PCOS and obesity, and small studies of lifestyle or bariatric weight loss report falls of 10 to 30 percent along with improvements in insulin and cycle regularity. The effect is modest and limited to physiological mild elevations; it does not treat a prolactinoma.
Review alcohol and herbal galactagogues
Preliminary evidenceAcute alcohol intake raises prolactin for several hours and chronic heavy drinking produces sustained elevations that fall within weeks of abstinence. Herbs sold to increase milk supply (fenugreek, fennel, blessed thistle, anise) are taken precisely because they may stimulate prolactin; stopping them before testing, and during a work-up, removes a possible confounder.
Do not stop prescribed medication to lower prolactin without discussing it with your prescriber; abrupt withdrawal of antipsychotics or antidepressants can be dangerous.
When to see a clinician promptly
- Sudden severe headache with visual loss, double vision, drowsiness or collapse in anyone with a known or suspected pituitary tumour: possible pituitary apoplexy (bleeding into the tumour), an emergency.
- Gradual loss of the outer edges of vision, persistent headaches, or a prolactin confirmed above 200 to 250 ng/mL: needs a pituitary MRI and endocrine referral within weeks.
- Inability to produce milk after childbirth together with extreme fatigue, dizziness, failure of periods to return or low blood pressure: possible Sheehan's syndrome, which can include life-threatening cortisol deficiency.
- Absent periods for three months or more, unexplained nipple discharge (especially bloody or from one breast, which needs breast assessment as well), or infertility, with any raised prolactin.
- Men with erectile dysfunction, low libido, breast enlargement or infertility and a raised prolactin.
- A high prolactin on an antipsychotic with symptoms (missed periods, galactorrhea, sexual dysfunction, bone loss), to discuss options with your psychiatrist rather than stopping the drug yourself.
Frequently asked questions
What is a normal prolactin level?
For non-pregnant women most labs quote an upper limit of about 20 to 29 ng/mL (often 25), and for men about 15 to 20 ng/mL. In pregnancy levels climb to 100 to 400 ng/mL by the third trimester and stay high while breastfeeding. If your lab reports in mIU/L, divide by about 21 to convert to ng/mL. A value a few points over the limit is very often stress, timing or macroprolactin, and is repeated before anything is concluded.
What causes high prolactin?
In order of how often they turn up: medications (antipsychotics such as risperidone, the anti-nausea drugs metoclopramide and domperidone, some antidepressants, opioids and oral estrogen), the stress of the blood draw or recent exercise, sex or breast stimulation, pregnancy and breastfeeding, an underactive thyroid, macroprolactin (an inactive form the assay counts), chronic kidney disease, a prolactin-secreting pituitary tumour, and other pituitary masses that press on the stalk. Levels above 200 to 250 ng/mL without a drug cause nearly always mean a prolactinoma.
What prolactin level indicates a prolactinoma?
There is no exact line, but the Endocrine Society treats a single value above 250 ng/mL (after excluding drugs) as diagnostic, and a value above 200 is highly suggestive. Microadenomas under 1 cm usually produce 100 to 250 ng/mL, macroadenomas over 250 and often several thousand. Levels of 25 to 100 are more often drugs, thyroid disease, kidney disease, macroprolactin or stalk compression by a non-prolactin tumour than a prolactinoma, though small prolactinomas can sit in this range. An MRI settles it.
What is macroprolactin and should I worry about it?
Macroprolactin is prolactin bound to an IgG antibody into a large complex that the body cannot use but that most lab assays count as real hormone. It explains 10 to 25 percent of raised prolactin results, typically values of 25 to 100 ng/mL in people with no symptoms. The lab checks for it by precipitating the sample with polyethylene glycol and measuring what is left; if less than 40 percent of the prolactin remains, you have macroprolactinemia, the active prolactin is usually normal, and no imaging or treatment is needed. Ask whether your lab screened for it.
Can stress raise prolactin levels?
Yes. Prolactin is a stress-responsive hormone: a painful or anxious blood draw, a sleepless night, a hard workout, sex or a breast examination in the hours before the test can raise it to 30 to 50 ng/mL. Guidelines recommend a repeat on a quiet morning two or more hours after waking, or two to three samples drawn through a cannula 15 to 20 minutes apart when the first result is only mildly raised. Stress does not produce levels in the hundreds; those need another explanation.
How does high prolactin affect fertility?
Prolactin suppresses the hypothalamic hormone GnRH, so the pituitary releases less LH and FSH, the ovaries stop ovulating regularly, estrogen falls and periods become irregular or stop; in men testosterone and sperm production fall. Hyperprolactinemia accounts for a meaningful share of anovulatory infertility and is one of the most treatable causes: dopamine-agonist tablets restore ovulation in 80 to 90 percent of women and normalise testosterone in most men. Mild elevations with regular ovulatory cycles usually do not need treatment for fertility.
Which medications raise prolactin?
Antipsychotics are the biggest group: risperidone, paliperidone, amisulpride, haloperidol and the older phenothiazines raise it in most users, sometimes above 200 ng/mL, while aripiprazole, quetiapine and clozapine mostly do not. Metoclopramide and domperidone (for nausea and reflux) are potent raisers. SSRIs, tricyclics, opioids, methadone, verapamil, methyldopa, intravenous cimetidine, oral estrogen and some herbal galactagogues (fenugreek, fennel) raise it more modestly. Never stop a prescribed drug on your own; a supervised three-day pause and retest, or a switch to a prolactin-sparing alternative, is arranged with the prescriber.
Do I need to fast for a prolactin test, and what time should it be done?
Fasting is not required by the Endocrine Society guideline, though some labs ask for it because a large meal can raise prolactin slightly. Timing matters more: prolactin peaks during sleep and is highest in the first hour after waking, so the sample is best drawn two or more hours after you wake, when you are rested and unstressed. Avoid exercise, sex, nipple stimulation and a breast examination in the hours before, and tell the lab about every medication and supplement.
References
- Prolactin levels. MedlinePlus, US National Library of Medicine (2023)View source
- Melmed S, Casanueva FF, Hoffman AR, et al.. Diagnosis and treatment of hyperprolactinemia: an Endocrine Society clinical practice guideline. Journal of Clinical Endocrinology and Metabolism (2011)View source
- Petersenn S, Fleseriu M, Casanueva FF, et al.. Diagnosis and management of prolactin-secreting pituitary adenomas: a Pituitary Society international consensus statement. Nature Reviews Endocrinology (2023)
- Molitch ME. Drugs and prolactin. Pituitary (2008)
- Fahie-Wilson M, Smith TP. Determination of prolactin: the macroprolactin problem. Best Practice and Research Clinical Endocrinology and Metabolism (2013)
- Frieze TW, Mong DP, Koops MK. Hook effect in prolactinomas: case report and review of literature. Endocrine Practice (2002)
- Vilar L, Vilar CF, Lyra R, Freitas MDC. Pitfalls in the diagnostic evaluation of hyperprolactinemia. Neuroendocrinology (2019)
- Milewicz A, Gejdel E, Sworen H, et al.. Vitex agnus castus extract in the treatment of luteal phase defects due to latent hyperprolactinemia: results of a randomized placebo-controlled double-blind study. Arzneimittelforschung (1993)
- Haddad PM, Wieck A. Antipsychotic-induced hyperprolactinaemia: mechanisms, clinical features and management. Drugs (2004)
- Hyperprolactinemia. Merck Manual Professional Version (2024)
- Prolactinoma. Mayo Clinic (2023)View source
- Casanueva FF, Molitch ME, Schlechte JA, et al.. Guidelines of the Pituitary Society for the diagnosis and management of prolactinomas. Clinical Endocrinology (2006)
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