Drug Induced Renal Disorders occur when certain medications cause injury to the kidneys. The kidneys play a major role in filtering drugs and their metabolites, which makes them highly vulnerable to toxic damage. Drug-induced kidney problems range from mild, reversible changes to severe renal failure. Early identification and prevention can significantly reduce kidney damage.
Mechanisms of Drug-Induced Kidney Injury
- Reduced renal blood flow (hemodynamic changes)
- Direct tubular toxicity
- Acute interstitial nephritis (allergic-type reaction)
- Crystal deposition inside renal tubules
- Obstruction of urinary flow
- Thrombotic microangiopathy
Common Nephrotoxic Drugs
1. NSAIDs
- Ibuprofen
- Diclofenac
- Indomethacin
Cause reduced renal blood flow and interstitial nephritis.
2. Aminoglycoside Antibiotics
- Gentamicin
- Amikacin
Cause dose-related tubular toxicity.
3. Vancomycin
Risk increases with high doses or use with other nephrotoxic drugs.
4. Radiographic Contrast Agents
Can cause contrast-induced nephropathy, especially in diabetics and CKD patients.
5. Chemotherapy Drugs
- Cisplatin
- Methotrexate
6. ACE Inhibitors and ARBs
May reduce GFR in patients with renal artery stenosis.
7. Diuretics
May cause dehydration and electrolyte imbalance leading to renal dysfunction.
Clinical Features
- Sudden decrease in urine output
- Swelling of legs and face
- Nausea and vomiting
- Fatigue
- High creatinine levels
- Electrolyte abnormalities (e.g., high potassium)
Diagnosis
- Blood tests: serum creatinine, BUN
- Urine tests: protein, blood, casts
- Ultrasound: to rule out obstruction
- Kidney biopsy if needed to confirm type of injury
Management
1. Stop the Offending Drug
This is the most important step in recovery.
2. Supportive Care
- Maintain proper hydration
- Monitor electrolytes
- Correct high potassium levels
- Manage fluid overload with diuretics (if appropriate)
3. Specific Treatments
- Corticosteroids for drug-induced interstitial nephritis
- Urinary alkalinization for methotrexate toxicity
- Dialysis for severe renal failure
Complications
- Acute Kidney Injury (AKI)
- Chronic Kidney Disease (CKD)
- Electrolyte imbalance
- Fluid overload
- Permanent renal damage
Prevention
- Avoid unnecessary nephrotoxic drugs
- Use the lowest effective dose
- Ensure adequate hydration
- Monitor kidney function regularly
- Avoid combination of multiple nephrotoxic agents
- Adjust doses in CKD patients
Patient Counseling
- Avoid self-medication with painkillers like NSAIDs
- Inform the doctor about all medications being taken
- Stay hydrated during fever, vomiting, or diarrhea
- Report reduced urine output immediately
- Attend regular kidney function tests
Detailed Notes:
For PDF style full-color notes, open the complete study material below: