Before your blood test
Do SSRIs and antipsychotics raise prolactin on a blood test?
Short answer
Yes — medication is the most common non-pregnancy cause of a high prolactin. Antipsychotics that block dopamine (risperidone, haloperidol and others) raise it most; SSRIs and some other antidepressants raise it modestly; metoclopramide, some blood-pressure drugs and estrogen also raise it. A prolactin drawn on one of these is often high without any pituitary problem. Draw prolactin fasting, rested, at least an hour after waking, and tell the clinician every medication you take — a high result is usually repeated, and in some cases the prescriber will consider whether the medicine explains it before any imaging. Never stop a psychiatric medication on your own.
Medically reviewed by Youmna DiStefano, MD · Last reviewed September 2026
Which results does it affect?
| Marker | Direction | How long | What to do |
|---|---|---|---|
| Prolactin | raises | While taking; falls within days to weeks of a change the prescriber makes | List all medications with the order; a clinician interprets the level with the drug in mind [source] |
| Prolactin (antipsychotics: risperidone, paliperidone, haloperidol, others) | raises | While taking; the largest medication effect | Expected; a very high level on these drugs still gets a clinician's review, not an automatic MRI [source] |
| Prolactin (SSRIs and other antidepressants) | can raise | While taking; usually a modest rise | Mention the medication; repeat under standard conditions before further work-up [source] |
| Estradiol, testosterone, LH, FSH | can lower | While prolactin stays high | Irregular cycles, low libido or low testosterone on these medications: check prolactin alongside the sex hormones [source] |
| Prolactin after stress, exercise, a meal or nipple stimulation | raises | Hours | Draw fasting, rested, one to two hours after waking; avoid strenuous exercise beforehand [source] |
Why do these medicines raise prolactin?
Dopamine is the brain's brake on prolactin release. Antipsychotics work by blocking dopamine receptors, so the brake comes off and prolactin rises — sometimes several-fold, and more in women than men. SSRIs act on serotonin, which indirectly loosens the same brake, so the rise is smaller and less consistent. Other common culprits are metoclopramide (a dopamine blocker used for nausea), verapamil, methyldopa and estrogen-containing contraception.
Because the mechanism is a normal response to the drug, the result is real — prolactin is genuinely high — but it does not point to a pituitary tumor. The clinical question becomes whether the level is causing symptoms (irregular or absent periods, milky discharge, low libido, low testosterone) and whether the prescriber wants to adjust the medication.
How is a high prolactin on medication worked up?
A single high value is usually repeated under standard conditions: fasting, rested, at least an hour after waking, no strenuous exercise or nipple stimulation beforehand, and no recent blood draw stress. The clinician reviews the medication list, checks for pregnancy where relevant, and looks at thyroid function, because an underactive thyroid also raises prolactin. Only when the level is high out of proportion to the medication, or symptoms suggest a pituitary cause, does imaging follow. Any change to a psychiatric medication is the prescriber's decision — stopping on your own to 'fix' a lab value is not safe.
Common questions
Will my SSRI make my prolactin high?
It can, usually modestly. If your prolactin comes back high on an SSRI, the standard next step is a repeat under proper conditions and a medication review, not imaging.
Which medications raise prolactin the most?
Dopamine-blocking antipsychotics — risperidone, paliperidone and haloperidol among them — and metoclopramide. SSRIs, verapamil, methyldopa and estrogen raise it less.
Should I skip my medication before a prolactin test?
No. Take medications as prescribed and list them with the order. The clinician interprets the result knowing what you take; only the prescriber decides whether a change is warranted.
Educational content, not a diagnosis. Lab results are one input; a clinician interprets them with your history and exam.