Can Chemotherapy Cause Blood in Urine, and How to Cope

Yes, chemotherapy can sometimes cause blood in the urine (hematuria), most often by irritating or inflaming the bladder. This can range from mild pink urine to visible bleeding and clots, and it needs prompt attention to rule out infection and prevent complications. Some chemo drugs are known bladder irritants, and specialized prevention and management steps are available. ^{[1] [2]}

Why It Happens

• Bladder irritation from certain chemotherapy agents can cause urgency, burning with urination, or blood in urine; these symptoms may also signal a urinary infection, so testing is important. ^{[1] [2]}
• Specific alkylating agents (notably cyclophosphamide and ifosfamide) can cause a condition called hemorrhagic cystitis due to a toxic metabolite (acrolein) that injures the bladder lining. ^[3]
• The risk with ifosfamide is dose-related; hematuria has been reported in a wide range of patients, and preventive measures like strong hydration, fractionated dosing, and a protective drug called mesna can significantly lower the risk. ^[4]
• Prior bladder radiation or certain other treatments may further increase the risk of hemorrhagic cystitis with ifosfamide. ^{[5] [6]}

Drugs Commonly Involved

• Cyclophosphamide and ifosfamide: most strongly linked with hemorrhagic cystitis through acrolein-related bladder toxicity. ^[3]
• Anthracyclines (for example, doxorubicin) can cause red/orange urine discoloration for up to 48 hours, which may be harmless pigment rather than true bleeding; however, visible blood or ongoing symptoms should still be evaluated. ^[7]

When to Call Your Care Team

• New urinary urgency, burning, or visible blood in urine during chemotherapy should prompt a call to your oncology team; they may request a urine test to check for infection or inflammation. ^{[1] [2]}
• Any fever with urinary symptoms should be treated as urgent due to infection risks during chemotherapy. ^[8]

Immediate Self‑Care Steps

• Hydration: Drink plenty of fluids to dilute urine and reduce bladder contact time with irritants unless your clinician has given you fluid restrictions. ^[9]
• Frequent urination: Empty your bladder regularly and avoid holding urine to minimize bladder exposure to metabolites. ^[9]
• Time dosing (for oral cyclophosphamide): Taking the dose earlier in the day can reduce overnight metabolite dwell time in the bladder, if this matches your prescribed schedule. ^[10]
• Track symptoms: Note urine color changes, burning, frequency, clots, lower abdominal pain, or fever to report accurately to your team. ^{[1] [2]}

Medical Prevention and Treatments

• Mesna protection: Mesna is specifically indicated to reduce the risk of ifosfamide‑induced hemorrhagic cystitis; it binds toxic metabolites in urine to protect the bladder. It lowers risk but does not prevent all cases. ^{[11] [12]}
• Hydration protocols: Oncologists often pair mesna with vigorous IV/oral hydration and sometimes diuretics to flush the bladder. This combined approach helps reduce hematuria rates. ^[4]
• Dosing strategies: Fractionating the total daily dose rather than giving a single large dose can lessen bladder toxicity with ifosfamide. ^{[4] [5]}
• Rapid evaluation: If hematuria appears, clinicians may test urine, check blood counts (for platelet-related bleeding risk), adjust chemo, optimize mesna/hydration, and, in severe cases, use bladder irrigation or involve urology. ^{[4] [3]}

Distinguishing Benign Discoloration from Bleeding

• Short‑term pink/red/orange urine after certain anthracyclines can be a temporary drug‑related discoloration, not true bleeding. If color persists beyond expected time or is accompanied by pain, frequency, burning, clots, or fever, contact your team. ^{[7] [1]}

Practical Tips at Home

• Stay ahead of hydration the day before, the day of, and the day after bladder‑irritating chemotherapy if your clinician advises it. ^[9]
• Urinate every 2–3 hours while awake, including before sleep. ^[9]
• Avoid bladder irritants like caffeine and alcohol if they worsen symptoms, and maintain gentle activity to promote circulation. ^[1]
• Keep a symptom diary with dates, timing relative to chemo doses, and severity to aid clinical decisions. ^{[1] [2]}

Red Flags Requiring Urgent Care

• Passing clots, difficulty urinating, severe lower abdominal pain, or lightheadedness. ^[4]
• Fever or chills with urinary symptoms, given the risk of low white counts during chemotherapy. ^[8]
• Persistent or heavy bleeding despite hydration and mesna. ^{[4] [11]}

Key Takeaways

• Blood in urine can be a side effect of chemotherapy due to bladder irritation or hemorrhagic cystitis, especially with cyclophosphamide or ifosfamide. Early reporting allows prompt testing and treatment. ^{[1] [3]}
• Preventive strategies adequate hydration, frequent voiding, timing of oral doses, and mesna when indicated can reduce risk and severity. ^{[10] [4] [11]}
• Even mild symptoms deserve attention to exclude infection and to prevent progression. ^{[2] [1]}