What should I do if I experience hematuria (blood in urine) while taking Cialis (tadalafil)?

Hematuria While Taking Cialis: Immediate Action Required

If you experience blood in your urine (hematuria) while taking Cialis (tadalafil), you must seek urgent urologic evaluation regardless of whether the bleeding is visible (gross) or microscopic, and you should not attribute the hematuria to the medication alone. 1, 2, 3

Why This Matters

• Gross (visible) hematuria carries a 30-40% risk of underlying malignancy and requires urgent urologic referral even if the bleeding stops on its own 2, 3
• Medications like Cialis do not cause hematuria—they may only unmask underlying urinary tract pathology that requires investigation 1, 2, 4
• The American College of Physicians explicitly states that evaluation should proceed even in patients taking medications that affect bleeding 1

Immediate Steps to Take

1. Do Not Delay Medical Evaluation

• Contact a urologist immediately if you see visible blood in your urine 1, 3
• Even if the bleeding has stopped, urgent evaluation is still mandatory 1, 3
• Do not assume the Cialis is the cause and wait to see if it resolves 1, 2

2. Confirm True Hematuria

• If you haven't seen visible blood but a dipstick test was positive, request microscopic urinalysis showing ≥3 red blood cells per high-powered field to confirm true hematuria 1, 2, 4
• Dipstick tests have only 65-99% specificity and can produce false positives 1, 4

3. Provide Critical History to Your Doctor

• Smoking history (especially >30 pack-years increases risk) 2
• Occupational exposures to chemicals, dyes, benzenes, or aromatic amines 2, 3
• Any episodes of visible blood in urine, even if brief 1, 2
• Associated symptoms: flank pain, painful urination, irritative voiding symptoms, or weight loss 2, 3
• Other medications: anticoagulants or antiplatelet drugs (though these don't explain away hematuria) 1, 5

Required Urologic Workup

For Gross (Visible) Hematuria:

• Cystoscopy (camera examination of the bladder) is mandatory to exclude bladder cancer 2, 3
• CT urography (specialized CT scan with contrast) to evaluate kidneys and ureters for tumors or stones 2, 3
• Urine cytology to detect cancer cells, particularly in high-risk patients 2, 3
• Serum creatinine to assess kidney function 2, 3

For Microscopic Hematuria (≥3 RBCs/HPF):

• Risk stratification based on age, smoking history, and degree of hematuria determines the extent of workup 2
• Most patients still require cystoscopy and upper tract imaging (CT urography or ultrasound) 2, 4

Common Pitfalls to Avoid

Never Assume Cialis Is the Culprit

• While Cialis (tadalafil) is used to treat lower urinary tract symptoms in men with benign prostatic hyperplasia, it does not cause hematuria 6, 7
• Phosphodiesterase-5 inhibitors like Cialis work by relaxing smooth muscle and improving blood flow, but they are not associated with causing blood in urine 7
• One case report documented epistaxis (nosebleed) with Cialis, but hematuria is not a recognized side effect 8

Don't Delay Because Bleeding Stopped

• Self-limited gross hematuria still requires full evaluation due to high malignancy risk 1, 3
• Intermittent bleeding can be characteristic of bladder or kidney tumors 2, 3

Don't Skip Evaluation Due to Other Medications

• If you're taking anticoagulants (warfarin, rivaroxaban, apixaban) or antiplatelet drugs (aspirin, clopidogrel), these increase the risk of hematuria but do not explain it away 1, 5, 9
• Anticoagulants may unmask underlying pathology that requires investigation 1, 5
• Research shows rivaroxaban and warfarin are most frequently associated with hematuria episodes, but this mandates evaluation, not dismissal 9

What Your Doctor Will Look For

Urologic (Non-Kidney) Causes:

• Bladder cancer (most common malignancy found in hematuria workup) 2, 3
• Kidney cancer or upper urinary tract tumors 2, 3
• Kidney or ureteral stones (usually causes painful hematuria) 2
• Benign prostatic hyperplasia (BPH)—relevant since you're taking Cialis, which treats BPH symptoms 1, 6
• Urinary tract infection (though typically causes other symptoms) 2

Kidney (Glomerular) Causes:

• If urinalysis shows dysmorphic red blood cells (>80%), red cell casts, or significant proteinuria, this suggests kidney disease rather than urologic causes 2, 4
• This would require nephrology referral instead of or in addition to urology 2, 4

Special Considerations for Cialis Users

• Cialis (tadalafil) is FDA-approved for treating lower urinary tract symptoms associated with BPH 1, 6
• It improves urinary symptoms by 3-10 points on the International Prostate Symptom Score through smooth muscle relaxation 6, 7
• However, hematuria is not a known side effect of Cialis and should never be attributed to the medication without thorough investigation 1, 2
• The one cardiac guideline mentioning tadalafil notes a 48-hour window for nitrate contraindication in heart attack patients, but this is unrelated to hematuria 1

Follow-Up Protocol

If initial workup is negative but hematuria persists:

• Repeat urinalysis at 6,12,24, and 36 months 2, 3
• Monitor blood pressure at each visit 2, 3
• Immediate re-evaluation if gross hematuria recurs, microscopic hematuria worsens significantly, new urologic symptoms develop, or hypertension/proteinuria appears 2, 3

Bottom Line

Blood in urine while taking Cialis requires the same urgent evaluation as hematuria from any other cause—do not delay seeking urologic consultation. 1, 2, 3 The medication does not explain the bleeding and should not prevent thorough investigation for potentially serious underlying conditions, including malignancy. 1, 2