What medications should I start a patient with Chronic Kidney Disease (CKD) stage 4 on while waiting for a nephrology consultation?

Medication Management for CKD Stage 4 While Awaiting Nephrology Consultation

For patients with CKD stage 4, start with a renin-angiotensin system inhibitor (ACEi or ARB), an SGLT2 inhibitor if diabetic, and consider loop diuretics for volume management while awaiting nephrology consultation. 1

Blood Pressure Management

• Start with either an ACEi or ARB at reduced doses appropriate for CKD stage 4 (eGFR <30 ml/min/1.73m²) 1, 2
• For ACEi (like lisinopril), start at half the usual dose (2.5 mg daily) in patients with creatinine clearance ≤30 ml/min 2
• Target systolic blood pressure of <120 mmHg when tolerated, using standardized office BP measurement 1
• Monitor serum creatinine and potassium within 2-4 weeks of starting or increasing the dose of ACEi/ARB 1
• Continue ACEi or ARB therapy unless serum creatinine rises by more than 30% within 4 weeks of initiation 1
• Consider reducing or discontinuing ACEi/ARB if symptomatic hypotension or uncontrolled hyperkalemia occurs despite treatment 1, 3
• Avoid combination therapy of ACEi and ARB due to increased risk of hyperkalemia and acute kidney injury 1

Volume Management

• Consider loop diuretics (rather than thiazides) for volume control in patients with advanced CKD showing signs of volume overload 1
• Recommend dietary sodium restriction (<2g of sodium per day) to enhance blood pressure control 1
• Monitor for signs of volume depletion which can worsen renal function in patients on ACEi/ARB therapy 4, 3

For Patients with Diabetes

• Start an SGLT2 inhibitor if the patient has type 2 diabetes and eGFR ≥20 ml/min/1.73m² 1
• Continue SGLT2 inhibitor even if eGFR falls below 20 ml/min/1.73m², unless not tolerated or kidney replacement therapy is initiated 1
• Consider GLP-1 receptor agonists for patients with type 2 diabetes and high cardiovascular risk 5, 6

Lipid Management

• Start statin therapy for cardiovascular risk reduction 5, 6
• For patients with CKD stage 4, target LDL-C ≤55 mg/dl (1.4 mmol/l) and an LDL-C reduction of 50% or more from baseline 5
• Consider adding ezetimibe if LDL targets are not achieved with maximally tolerated statin dose 5

Monitoring and Follow-up

• Check serum creatinine, potassium, and blood pressure within 2-4 weeks of starting ACEi/ARB therapy 1, 3
• Monitor for hyperkalemia, which can be managed with dietary potassium restriction and potassium binders rather than immediately reducing ACEi/ARB dose 1
• Assess for uremic symptoms that may indicate need for dialysis initiation 7
• Urgent nephrology referral is indicated for patients with uremic symptoms, BUN >100 mg/dL, or altered mental status 7, 1

Important Considerations and Caveats

• The risk of acute kidney injury is higher in CKD stages 4-5 than in earlier CKD stages, requiring careful medication management 1, 8
• In older individuals with CKD, diastolic BP is often low due to arterial stiffness; intensive BP lowering may accelerate the need for kidney replacement therapy 1
• There is limited evidence from randomized controlled trials for specific BP targets in CKD stage 4, as most trials excluded patients with advanced CKD 1
• The benefits of ACEi/ARB therapy in CKD stage 4 must be balanced against potential risks of hyperkalemia and worsening renal function 3, 8
• Avoid NSAIDs as they can worsen kidney function, especially in combination with ACEi/ARB therapy 9, 4

While awaiting nephrology consultation, focus on blood pressure control, appropriate medication selection based on comorbidities, and close monitoring of renal function and electrolytes to prevent complications of advanced CKD.