Amlodipine Dosage and Administration
For adult hypertension, amlodipine should be started at 5 mg once daily with a maximum dose of 10 mg once daily. 1
Adult Dosing
- Initial dose for hypertension: 5 mg once daily 1, 2
- Maximum dose: 10 mg once daily 1
- For elderly, fragile patients or those with hepatic insufficiency: Start with 2.5 mg once daily 1
- For angina (stable or vasospastic): 5-10 mg once daily, with lower doses suggested for elderly and hepatic insufficiency patients 1
- For coronary artery disease: 5-10 mg once daily (most patients require 10 mg for adequate effect) 1
- Dose titration: Wait 7-14 days between dose adjustments to assess response 1
Pediatric Dosing
- For children ages 6-17 years with hypertension: 2.5-5 mg once daily 1, 3
- Maximum pediatric dose: 5 mg daily (doses exceeding 5 mg have not been studied in pediatric patients) 1
- For children <6 years: Not FDA approved 1
- For pulmonary hypertension in children: Starting dose 0.1-0.3 mg/kg/day with a dose range of 2.5-7.5 mg/day (maximum 10 mg/day) 3
Pharmacokinetic Considerations
- Bioavailability: 60-80% 4
- Onset of action: Gradual, with peak plasma concentration occurring 6-8 hours after dosing 4
- Half-life: 36-45 hours, allowing for once-daily dosing 4, 5
- Steady state: Achieved after 7-10 days of once-daily administration 4
- Plasma concentration fluctuation between doses: Only 20-25% with once-daily dosing 4
Special Populations
- Elderly patients: Start with 2.5 mg once daily due to decreased clearance 1
- Hepatic impairment: Start with 2.5 mg once daily 1
- Renal impairment: No specific dose adjustment required 1
Monitoring and Titration
- Assess blood pressure response after 7-14 days before considering dose adjustment 1
- Early dose increases (before 6 weeks) show no advantage over maintaining the initial 5 mg dose 6
- The minimum effective dose for hypertension is 2.5 mg 7
- Dose-related reduction in blood pressure occurs with once-daily dosing 7
Common Side Effects
Clinical Pearls
- Amlodipine can be compounded into stable extemporaneous suspensions for patients unable to swallow tablets 3
- Unlike some calcium channel blockers, amlodipine has minimal negative effects on cardiac conduction and contractility 5
- Amlodipine can be safely combined with other antihypertensive agents including ACE inhibitors, beta-blockers, and diuretics for additional blood pressure lowering effects 2
- No clinically significant effects on pulse rate, ECG, or body weight have been observed 7
- Amlodipine does not show development of tolerance with long-term use 2
- Unlike immediate-release nifedipine, amlodipine can be used without concomitant beta-blockade due to its gradual onset of action 3