🧪 Fasting serum prolactin: - Normal: < 20 ng/mL (625 mU/L) in women; < 15 ng/mL (375 mU/L) in men - Raised PRL → exclude macroprolactin
⬇️ Testosterone often low (men)
🧠 Pituitary MRI + gadolinium → microadenoma / macroadenoma
👁️ Visual field testing if suprasellar extension
🧪 Check pituitary panel (FSH, LH, TSH, cortisol, etc.)
❤️ Echocardiogram before starting cabergoline (rare valvopathy risk)

Cabergoline is first-line treatment for prolactinoma and works by stimulating pituitary D2 receptors to suppress prolactin secretion and shrink tumour size, often restoring normal gonadal function. Concern about heart valve disease arises because cabergoline can stimulate 5-HT2B serotonin receptors on cardiac valve fibroblasts, potentially causing fibroproliferative thickening; however, the clinically significant risk signal came from Parkinson’s disease patients exposed to much higher daily and cumulative doses. In endocrine practice, where doses are typically 0.25–1 mg twice weekly, observational data show that moderate–severe valvular disease is rare and the absolute risk appears very low. UK practice usually includes a baseline echocardiogram and periodic surveillance (often at 1 year, then 1–2 yearly if higher dose or long duration), which further mitigates risk. Overall, at standard prolactinoma doses, the benefits of prolactin normalisation and tumour control generally outweigh the small theoretical risk of valvulopathy.

🧾 Differential Diagnosis

Physiological ↑ PRL: pregnancy, lactation 🤰
Drug-induced ↑ PRL (antipsychotics, antidepressants, metoclopramide)
Non-secreting adenoma pressing on pituitary stalk (“stalk effect”)

💊 Management

✨ Medical (first-line) → only pituitary tumour usually managed medically
🚀 Dopamine agonists (cabergoline 0.5–1 mg/week in 2 doses; bromocriptine less used) → shrink tumour + normalise PRL
📉 Recurrence risk ↑ if residual tumour visible on MRI when treatment is stopped
❤️ Valvopathy risk with cabergoline is very low at standard doses (<2 mg/week)
🔪 Surgery (transsphenoidal hypophysectomy) → rarely indicated (failure, intolerance, vision compromise)
☢️ Radiotherapy reserved for refractory or large tumours
⚠️ Malignant prolactinomas = extremely rare

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Prolactinoma

📖 About

🩺 Clinical Features

🔍 Investigations

🧾 Differential Diagnosis

💊 Management

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