Naproxen can reduce kidney blood flow, worsen blood-pressure control, and contribute to fluid retention in susceptible people. This worksheet helps capture context for a clinician; it does not diagnose kidney injury from a home reading or urine observation.
Download the printable 12-page kidney and blood-pressure guide (PDF)
Who needs extra caution
- Chronic kidney disease, prior acute kidney injury, heart failure, high blood pressure, liver disease, diabetes, older age, or frailty.
- Vomiting, diarrhea, fever, heavy sweating, poor fluid intake, fasting, or another cause of dehydration.
- A diuretic together with an ACE inhibitor or ARB, or other medicines whose exposure or effect depends on kidney function.
- Repeated, higher, or prescription-strength NSAID exposure rather than a clearly bounded short course.
What to monitor
Urine: record frequency and a meaningful change from normal. Dark or cloudy urine is not specific; infection, blood, concentration, liver problems, or muscle injury may need testing. Inability to urinate or a marked reduction needs prompt care.
Fluid: note new ankle or leg swelling, rapid weight change, increasing breathlessness, and whether symptoms are one-sided or both-sided. Do not independently increase a diuretic or drink excessive fluid when heart or kidney disease imposes limits.
Blood pressure: use a validated upper-arm cuff of the correct size. Sit quietly, support the arm, repeat an unexpected reading, and record pain, caffeine, decongestants, dose time, and missed medicines. Follow personal thresholds supplied by the treating clinician.
Laboratory context: creatinine, estimated kidney function, electrolytes, and sometimes a blood count may be selected according to risk and duration. A normal old result does not guarantee safety during a new dehydrating illness.
When to escalate
Seek prompt assessment for markedly reduced urine, rapidly increasing swelling, persistent vomiting/diarrhea, or a sustained blood-pressure change. Call emergency services for severe breathlessness, chest pressure, fainting, confusion, stroke signs, or a very high blood-pressure reading accompanied by serious symptoms.