Losartan and Nipple Discharge
Losartan is not a recognized cause of nipple discharge. The available evidence on losartan's adverse effects does not identify nipple discharge as a documented side effect, and nipple discharge guidelines do not list angiotensin II receptor antagonists among causative medications 1, 2.
Understanding the Disconnect
When evaluating nipple discharge in a patient taking losartan, the medication is unlikely to be the culprit:
- Losartan's documented adverse effects include dizziness (the only drug-related effect noted in clinical trials), rare angioedema, and rare acute hepatitis, but not nipple discharge or galactorrhea 1, 2
- Physiologic nipple discharge (galactorrhea) is typically caused by hyperprolactinemia from antipsychotics, pituitary tumors, and endocrine disorders—not from antihypertensive agents like losartan 3
- The withdrawal rate from losartan due to adverse effects (2.3%) is actually lower than placebo (3.7%), indicating excellent tolerability 1
Clinical Approach to This Patient
Evaluate the nipple discharge on its own merits rather than attributing it to losartan:
Characterize the discharge type:
- Physiologic discharge: bilateral, multiple ducts, provoked (not spontaneous), white/green/yellow color—requires no imaging if screening mammography is current 4, 5
- Pathologic discharge: spontaneous, unilateral, single-duct, serous or bloody—requires diagnostic mammography and ultrasound regardless of medication history 4, 5
Risk stratification for pathologic discharge:
- Malignancy risk ranges from 11-16% in women with pathologic discharge 5
- In men, nipple discharge carries a 23-57% malignancy risk and warrants aggressive evaluation 4
- Age matters: malignancy risk is 3% in patients <40 years, 10% in ages 40-60, and 32% in those >60 years 4
Imaging algorithm for pathologic discharge:
- First-line: diagnostic mammography of the symptomatic breast 4
- Second-line: ultrasound of the retroareolar region with special techniques (standoff pad, rolled-nipple maneuvers) 4, 5
- Third-line: ductography or breast MRI if mammography and ultrasound are negative 4
- Definitive management: surgical duct excision provides both diagnosis and treatment, even with negative imaging 5
Common Pitfall
Do not dismiss pathologic nipple discharge as a medication side effect without proper evaluation. While medications can cause galactorrhea (milky discharge), watery, serous, serosanguineous, or bloody discharge requires full workup regardless of medication history, as 13.3% of such cases are malignant 6.