Patient handout

Hyperprolactinaemia evaluation (exclude before prolactinoma)

PRODUCTION

1. Your condition

This handout is for hyperprolactinaemia evaluation (exclude before prolactinoma). Your care team identified this based on: incidental / screening elevated serum prolactin — finding, not diagnosis (endo soc 2011 melmed).

Other reasons your team may use this plan: woman: galactorrhoea ± oligo/amenorrhoea ± infertility (endo soc 2011 melmed); man: low libido / erectile dysfunction / gynaecomastia / infertility (pituitary soc 2023 petersenn); antipsychotic / metoclopramide / ssri / opioid / verapamil / oestrogen started — drug-induced surveillance (endo soc 2011 melmed).

2. Your medications

Take these medications exactly as prescribed. Do not stop or change a dose without talking to your provider.

Medication	Starting dose	How	When	What it does
repeat resting non-stressed serum prolactin	—	—	—	Endo Soc 2011 (PMID 21296991) — a single resting non-stressed value above the reference confirms; dynamic testing is NOT recommended; repeat reclassifies stress artifact to normal
β-hCG / pregnancy & lactation screen	—	—	—	Endo Soc 2011 (PMID 21296991) — pregnancy/lactation is the leading physiologic cause; a positive β-hCG halts the sieve

Plan: Hyperprolactinaemia cause-directed ladder — confirm → physiologic → drug deprescribe/swap → treat hypothyroidism → macroprolactin PEG (reassure) → hook-effect dilution → ROUTE true prolactinoma (Endo Soc 2011 Melmed; Pituitary Soc 2023 Petersenn)

3. Your action plan

Use these zones to know what to do based on how you feel.

GREEN — Cause found and addressed (drug, thyroid, macroprolactin, physiologic)

If you have:

A clear reversible cause was identified (a medicine, thyroid, pregnancy, or a harmless lab variant)
Prolactin is improving after the cause was treated or the medicine changed
No headaches or vision changes

Do this:

Keep the follow-up prolactin blood test your provider arranged (Endo Soc 2011 Melmed)
If your raised prolactin is a harmless lab variant (macroprolactin), no treatment or scans are needed — reassurance only (Kalsi PMID 30269265)
Do NOT stop a psychiatric medicine on your own — any change is made together with your psychiatrist (Endo Soc 2011 Melmed)
If you take thyroid medicine for an underactive thyroid, take it consistently and keep thyroid checks

YELLOW — Symptoms or an unexplained result that needs more workup

If you have:

Milky breast discharge, irregular/absent periods, low sex drive, or fertility concerns
Prolactin stays high after the likely cause was addressed
You are planning a pregnancy

Do this:

Attend the further tests your provider orders (repeat prolactin, thyroid, kidney, possibly a pituitary MRI) (Endo Soc 2011 Melmed)
Bring an up-to-date list of ALL your medicines including psychiatric medicines (Endo Soc 2011 Melmed)
Tell your provider if you are planning a pregnancy so the right pathway is followed (Molitch PMID 10649822)

Call your provider if:

New or worsening milky discharge, period changes, or fertility problems (Endo Soc 2011 Melmed)
Prolactin remains high despite addressing the suspected cause (Endo Soc 2011 Melmed)

RED — Possible pituitary mass pressing on nearby structures

If you have:

Sudden severe headache
New loss of side (peripheral) vision or double vision
Sudden severe headache with vomiting and visual loss (possible pituitary apoplexy)

Do this:

Go to the emergency department or call emergency services now
This can mean a pituitary mass affecting the nerves to the eyes — it needs urgent imaging and specialist care (Pituitary Soc 2023 Petersenn)
Bring your medication list

Call your provider if:

Always seek emergency care for sudden severe headache with vision loss (Pituitary Soc 2023 Petersenn)

4. When to seek emergency care

Call 911 or go to the nearest emergency room right away if you have:

Large/giant sellar mass with only mildly elevated prolactin — HOOK EFFECT until a 1:100 serial dilution proves otherwise (Pituitary Soc 2023 Petersenn; Barkan)
Macroadenoma with progressive bitemporal visual field loss or acute apoplectic headache + ophthalmoplegia (Pituitary Soc 2023 Petersenn)(life-threatening)

5. Follow-up

Idiopathic hyperprolactinaemia surveillance (most stable/resolve — Martin PMID 3980670); preconception counselling (prolactinoma pregnancy risk owned by endo.prolactinoma.core.v1 — micro ~1% vs macro 23% growth if DA stopped, Molitch PMID 10649822); reinforce that the antipsychotic is managed with psychiatry; return precautions (visual change, severe headache, new galactorrhoea) (Endo Soc 2011 Melmed; Pituitary Soc 2023 Petersenn)

6. Sources

Guideline: Endocrine Society 2011 Hyperprolactinaemia Clinical Practice Guideline (Melmed, JCEM 2011;96:273-88, PMID 21296991) + Pituitary Society 2023 international Consensus on prolactinomas (Petersenn, Nat Rev Endocrinol 2023;19:722-740, PMID 37670148); reconciled with cohort/RCT/ROC literature for the Bayesian sieve (PRL-magnitude LRs wired from Wright PMID 33966173, Leca PMID 33963239, Kyritsi PMID 29845629, Kim PMID 37057215, Kawaguchi PMID 25142896; hook effect Petakov PMID 9591215 / St-Jean PMID 8729527)