What should I do if I'm experiencing increased urination while taking losartan (angiotensin II receptor antagonist) for hypertension?

Losartan Does Not Cause Increased Urination—This Is Likely a Misattribution

Losartan itself does not have diuretic properties and should not cause increased urination. If you are experiencing more frequent urination while taking losartan, the most likely explanation is that you are also taking a diuretic medication (such as hydrochlorothiazide), which is commonly combined with losartan for blood pressure control 1.

Understanding Why You're Urinating More

If You're Taking Losartan Plus a Diuretic (e.g., Hydrochlorothiazide)

• The diuretic component is causing the increased urination, not the losartan. Thiazide diuretics like hydrochlorothiazide are specifically designed to increase urine output to lower blood pressure by reducing fluid volume 2, 3.

• Fixed-dose combinations of losartan/hydrochlorothiazide are widely prescribed and highly effective for hypertension management, with the diuretic component intentionally increasing urination 4, 3.

• This is the expected and therapeutic effect of the medication—the diuretic is working as intended to control your blood pressure 2.

If You're Taking Losartan Alone

• Losartan has mild uricosuric effects (increases uric acid excretion in urine) but does not function as a diuretic 5, 6.

• The increased urination you're experiencing is likely unrelated to losartan and may be due to:

  • Better blood pressure control improving kidney perfusion 1
  • Coincidental timing with increased fluid intake
  • An unrelated medical condition requiring evaluation 1

What You Should Do

Do Not Stop Your Medication Without Medical Guidance

• Abruptly discontinuing losartan can cause rebound hypertension and increase cardiovascular risk, particularly if you have chronic kidney disease or diabetes 1.

• Diuretics are a cornerstone of heart failure and hypertension management and should not be stopped without physician consultation 2.

Practical Management Strategies

• If the increased urination is bothersome, take your medication in the morning rather than evening to avoid nighttime bathroom trips 2.

• Monitor your daily weight—if you're losing more than 0.5-1.0 kg daily, your diuretic dose may be too high and should be discussed with your physician 2.

• Maintain moderate sodium restriction (3-4 g daily) to optimize the effectiveness of your blood pressure medications 2, 1.

When to Contact Your Physician

• Contact your doctor if you experience:
  • Excessive thirst or signs of dehydration (dry mouth, dizziness, dark urine) 2
  • Muscle cramps or weakness (may indicate electrolyte imbalances) 1, 3
  • Significant unintentional weight loss 2
  • Blood pressure readings consistently below your target range 3

Important Monitoring Considerations

• Your physician should check serum creatinine and potassium within 2-4 weeks after starting or adjusting losartan dosage 1.

• If you're on combination therapy with losartan/hydrochlorothiazide, electrolyte monitoring (potassium, sodium) is recommended within 1-2 weeks after dose escalation 3.

• A modest rise in serum creatinine (10-20%) after starting losartan is expected and hemodynamic in nature, not indicative of kidney injury unless persistent 1.

Common Pitfall to Avoid

• Do not reduce your fluid intake to compensate for increased urination—this can lead to dehydration and worsen kidney function, particularly if you're taking a diuretic 2, 1. Instead, maintain adequate hydration and discuss diuretic timing or dosage adjustment with your physician if the urination frequency is significantly impacting your quality of life.