Amlodipine Dosing for Dialysis Patients
No dose adjustment of amlodipine is required for patients on dialysis; the standard starting dose of 2.5-5 mg once daily can be used safely. 1, 2
Pharmacokinetic Rationale
Amlodipine's unique pharmacokinetic profile makes it particularly suitable for dialysis patients:
Hepatic metabolism predominates: Approximately 90% of amlodipine is converted to inactive metabolites via hepatic metabolism, with only 10% of the parent compound excreted renally 1
Minimal renal clearance impact: The pharmacokinetics of amlodipine are not significantly influenced by renal impairment, including end-stage renal disease requiring hemodialysis 1, 2
Not dialyzable: Amlodipine is approximately 93% protein-bound in plasma, and studies demonstrate that it is essentially not removed by hemodialysis, with only very low levels detectable in dialysate fluid 1, 3
Consistent elimination half-life: The terminal elimination half-life remains approximately 30-50 hours regardless of renal function, including in hemodialysis patients 1, 2, 3
Specific Dosing Recommendations
Standard dosing applies to all dialysis patients:
- Initial dose: 2.5-5 mg orally once daily 1
- Maximum dose: 10 mg once daily 1
- Timing: Can be administered at any time relative to dialysis sessions, as the drug is not removed by dialysis 3
The FDA label explicitly states that "patients with renal failure may therefore receive the usual initial dose" 1. This is supported by pharmacokinetic studies showing no tendency for drug accumulation in patients with renal dysfunction, including those on hemodialysis 2, 4, 3.
Clinical Evidence Supporting Standard Dosing
Cardiovascular outcomes data: A randomized controlled trial demonstrated that amlodipine reduced cardiovascular events compared with placebo in hemodialysis patients with hypertension 5. This evidence from KDIGO supports amlodipine as an effective calcium channel blocker option for blood pressure management in dialysis patients 5.
Safety profile in renal impairment: Studies in hypertensive patients with renal dysfunction, including those on hemodialysis, showed:
- Effective blood pressure control in 80-91% of patients 4, 6
- No significant aggravation of renal dysfunction 4
- Minimal adverse effects, with mild headache being the most common (2.9% incidence) 4
- No clinically significant accumulation with chronic dosing 4, 3
Practical Implementation
Dosing strategy:
- Start with 2.5-5 mg once daily regardless of dialysis schedule 1
- Titrate dose based on blood pressure response, not renal function 1
- Steady-state plasma levels are reached after 7-8 days of consecutive daily dosing 1
- No supplemental dosing needed post-dialysis 3
Monitoring considerations:
- Monitor blood pressure response as in patients without renal impairment 1
- No special laboratory monitoring required beyond standard blood pressure management 4
- Watch for typical calcium channel blocker side effects (peripheral edema, headache) rather than renal-specific concerns 4
Common Pitfalls to Avoid
Do not reduce the dose based solely on dialysis status - this is unnecessary and may lead to inadequate blood pressure control, as amlodipine pharmacokinetics are unaffected by renal impairment 1, 2, 3.
Do not time doses around dialysis sessions - unlike renally cleared medications, amlodipine does not require post-dialysis administration since it is not removed by dialysis 3.
Do not confuse amlodipine with other calcium channel blockers - while some calcium channel blockers may require dose adjustment in renal impairment, amlodipine's hepatic metabolism makes it uniquely suitable for unchanged dosing in dialysis patients 1.