Nephrotoxicity is a major risk and is monitored with BUN, creatinine, and urine output.
Before you read
Test yourself first: 3 questions
Question 1 of 3
A patient is prescribed an aminoglycoside antibiotic. To assess for nephrotoxicity, which combination of laboratory and drug-monitoring values is MOST appropriate?
Answer: A. Aminoglycosides are nephrotoxic and ototoxic, so renal function (BUN and creatinine) plus serum peak and trough drug levels are monitored. The trough level confirms the drug has cleared enough before the next dose.
Question 2 of 3
A client receiving IV furosemide reports new ringing in the ears. The nurse recognizes this as:
Answer: B. Tinnitus/hearing changes signal ototoxicity, a risk with rapid IV furosemide (and aminoglycosides). Slow the infusion and notify the provider; monitor hearing.
Question 3 of 3
A client on an aminoglycoside antibiotic (e.g., gentamicin) should be monitored for which toxicities?
Answer: B. Aminoglycosides are nephrotoxic and ototoxic — monitor renal function (creatinine), hearing/balance, and peak/trough levels.
Keep the streak going with more questions like these, each with a full rationale.
What is aminoglycosides?
Their two hallmark toxicities are nephrotoxicity (kidney damage) and ototoxicity (hearing and balance damage). Memory aid: the '-mycin' aminoglycosides hurt the ears and kidneys, so monitor peaks, troughs, and creatinine.
Key points to remember
- Nephrotoxicity is a major risk and is monitored with BUN, creatinine, and urine output.
- Ototoxicity can cause permanent hearing loss, tinnitus, vertigo, and balance problems.
- Peak and trough levels are drawn to keep the drug effective while avoiding toxicity; the trough is drawn just before the next dose.
- Toxicity risk rises with high troughs, dehydration, advanced age, and concurrent use of other nephrotoxic or ototoxic drugs (such as loop diuretics or vancomycin).
- They can cause neuromuscular blockade and respiratory depression, especially with anesthesia.
- They are not absorbed orally for systemic use, so they are given IV or IM for systemic infection.
Signs & symptoms
- Ototoxicity: tinnitus, hearing loss
- Nephrotoxicity: ↑ creatinine, ↓ UO
Nursing priorities
- Monitor renal function (BUN, creatinine) and intake and output throughout therapy.
- Draw peak and trough levels as ordered and report levels outside therapeutic range.
- Assess for hearing changes, ringing in the ears, dizziness, and balance problems.
- Ensure adequate hydration to protect the kidneys.
- Monitor for additive toxicity when combined with other nephrotoxic or ototoxic drugs.
Labs & values
Patient teaching
- Report any ringing in the ears, hearing changes, or dizziness immediately.
- Drink plenty of fluids to help protect your kidneys.
- Keep all lab appointments for blood level and kidney monitoring.
Red flags: report now
- Rising BUN/creatinine or decreasing urine output indicating nephrotoxicity.
- New hearing loss, tinnitus, or vertigo indicating ototoxicity.
- Elevated trough level indicating accumulation and toxicity risk.
- Respiratory depression or muscle weakness suggesting neuromuscular blockade.
References
Clinical references for this topic
