What is the treatment for hyperprolactinemia?

Treatment of Hyperprolactinemia

Dopamine agonists are the first-line treatment for hyperprolactinemia, with cabergoline preferred due to its better efficacy and tolerability compared to bromocriptine. 1

Diagnosis Before Treatment

Before initiating treatment, it's essential to:

• Confirm hyperprolactinemia with a single blood sample (repeat if mildly elevated)
• Identify underlying causes:
  • Review medications (antipsychotics, antidepressants, antihypertensives)
  • Check thyroid function (TSH, free T4)
  • Assess renal and liver function
  • Evaluate for symptoms of hypogonadism
  • Consider pituitary imaging to rule out prolactinoma

Treatment Algorithm

First-Line Treatment: Dopamine Agonists

1. Cabergoline:

   • Preferred agent due to better efficacy and tolerability 1
   • Starting dose: 0.25-0.5 mg/week
   • Gradually increase as needed based on prolactin response
   • Advantages: Once or twice weekly dosing, fewer side effects

2. Bromocriptine:

   • Alternative option, especially for women planning pregnancy 1, 2
   • Indicated for hyperprolactinemia-associated dysfunctions including amenorrhea, galactorrhea, infertility, and hypogonadism 2
   • More frequent dosing required
   • Higher incidence of side effects

Monitoring and Dose Adjustment

• Check prolactin levels 1 month after starting treatment 1
• Adjust dose based on:
  • Prolactin response
  • Side effects
  • Symptom improvement
• For prolactinomas, perform MRI after 3 months to verify tumor size reduction, then after 1 year, yearly for 5 years, and every 5 years if stable

Special Considerations

Prolactinomas

• Microprolactinomas: Medical therapy if symptomatic
• Macroprolactinomas: Medical therapy is first-line; consider surgery if:
  • Vision deteriorates or doesn't improve on medication
  • Dopamine agonist resistance occurs
  • Patient is intolerant to medication
  • Patient prefers surgery over long-term medication 1

Pregnancy

• Discontinue dopamine agonists when pregnancy is diagnosed unless there's risk of tumor expansion 1, 2, 3
• Close monitoring during pregnancy due to potential tumor growth
• Bromocriptine may be preferred for women planning pregnancy due to more safety data 2

Cardiac Monitoring

• Offer echocardiogram at the start of treatment with dopamine agonists 1, 3
• For patients on cabergoline:
  • Yearly echocardiography if receiving >2 mg/week
  • Every 5 years if on ≤2 mg/week 1
  • Discontinue if echocardiogram reveals new valvular regurgitation, restriction, or thickening 3

Drug-Induced Hyperprolactinemia

• If possible, discontinue the causative medication
• If medication cannot be withdrawn, avoid dopamine agonists
• Consider sex steroid replacement to prevent osteoporosis 4

Treatment Duration and Discontinuation

• Consider trial discontinuation after 2-3 years of normal prolactin levels
• After discontinuation, prolactin levels return to abnormal in only 20-30% of cases 4
• Continue monitoring prolactin levels after discontinuation
• Alternative approach: Reduce dose to lowest effective level that maintains normal prolactin

Common Pitfalls and Caveats

1. Failure to identify medication-induced hyperprolactinemia - Always review current medications before initiating dopamine agonists

2. Missing the "high-dose hook effect" - In patients with large pituitary lesions but only mildly elevated prolactin, perform serial dilutions of serum for accurate measurement 1

3. Inadequate monitoring for side effects - Watch for:

   • Hypotension (particularly during first days of treatment)
   • Somnolence and sudden sleep onset
   • Fibrotic complications (cardiac valvulopathy, pleural/pericardial effusions)
   • Retroperitoneal fibrosis 2, 3

4. Overlooking associated conditions - Evaluate for:

   • Hypothyroidism (common cause of hyperprolactinemia)
   • Chronic kidney disease
   • Low testosterone in men 1

5. Discontinuing treatment too early - Premature discontinuation may lead to symptom recurrence and tumor regrowth