Amlodipine Use in Renal Impairment
Amlodipine can be safely used in patients with impaired renal function without dose adjustment, as it is primarily metabolized hepatically and does not accumulate in renal impairment. 1, 2, 3
Pharmacokinetic Profile in Renal Disease
Amlodipine undergoes extensive hepatic metabolism (approximately 90% converted to inactive metabolites), with only 10% of the parent compound excreted renally, making it safe across all levels of kidney function 1.
The elimination half-life remains approximately 30-50 hours regardless of renal function status, from normal kidney function through dialysis-dependent patients 2, 3.
No dosage adjustment is necessary for patients with renal impairment, including those requiring hemodialysis 1, 2, 3.
Steady-state plasma concentrations are achieved after 7-8 days of consecutive dosing, with no significant drug accumulation observed in patients with renal dysfunction 1, 2.
Clinical Efficacy and Safety Data
In hypertensive patients with renal dysfunction (serum creatinine ≥1.5 mg/dL), amlodipine 2.5-5 mg daily achieved blood pressure control in 80% of patients over 8 weeks 4.
Amlodipine effectively controls blood pressure without significantly worsening renal function in most patients with chronic kidney disease 4, 5.
In therapeutic doses, amlodipine decreases renal vascular resistance and increases glomerular filtration rate and effective renal plasma flow without changing filtration fraction or causing proteinuria in hypertensive patients with normal renal function 1.
Important Limitations for Renoprotection
Amlodipine is inferior to ACE inhibitors and ARBs for renoprotection in patients with chronic kidney disease and should not be used as first-line monotherapy when renoprotection is the goal 6.
In the African-American Study of Kidney Disease, ramipril was superior to amlodipine for slowing kidney function loss despite identical blood pressure control 6.
In diabetic nephropathy, angiotensin receptor blockers were superior to amlodipine for preventing progressive kidney function loss and reducing proteinuria 6.
Appropriate Clinical Use
For CKD patients with proteinuria, ACE inhibitors or ARBs should be first-line therapy, with amlodipine reserved as add-on therapy when blood pressure targets (<130/80 mmHg) are not achieved 6.
Amlodipine is appropriate as second- or third-line therapy for blood pressure control in CKD patients already receiving ACE inhibitors or ARBs 6.
In a one-year prospective study comparing amlodipine to enalapril in hypertensive patients with renal dysfunction, both agents showed comparable effects on renal function, with amlodipine demonstrating better tolerability (9% dropout rate versus 33% with ACEI) 7.
Monitoring Considerations
While generally safe, mild increases in serum creatinine were observed in 11.4% of patients with renal impairment treated with amlodipine, though these changes were typically mild and did not require discontinuation 4, 5.
Unlike ACE inhibitors, amlodipine does not cause hyperkalemia, making it a safer option when potassium management is challenging 7.
Headache is the most common side effect, occurring in approximately 3% of patients with renal impairment 4, 5.