A comparative assessment of amlodipine and felodipine ER: pharmacokinetic and pharmacodynamic indices

Abstract

This study investigated potential therapeutic differences between Amlodipine 5 mg and Felodipine ER 10 mg in 12 normotensive/borderline hypertensive subjects by comparison of the plasma drug concentration-time profiles and the blood pressure and heart rate responses. There was significantly less trough-to-peak variability in plasma drug concentrations with amlodipine with a ratio of 67%, compared to 37% for felodipine. Correspondingly there was less variability with amlodipine in the blood pressure reductions across the dosage interval. Overall, amlodipine displayed a more consistent hypotensive effect across 24 hours and lower blood pressure values at trough, i.e. 24 hours post-dose.

Sympatho-excitatory responses to once-daily dihydropyridines in young versus older hypertensive patients: amlodipine versus felodipine extended release

“…These modest differences are unlikely to explain the clear differences in BP responses to the first dose between the two age groups. After chronic dosing of felodipine ER, plasma levels of felodipine showed modest further increases in both age groups compared with levels after the first dose, similar to the findings of Bainbridge et al [22]. In contrast, as expected from its long elimination half-life [22], in both age groups plasma levels of amlodipine markedly increased with chronic dosing.…”

“…After chronic dosing of felodipine ER, plasma levels of felodipine showed modest further increases in both age groups compared with levels after the first dose, similar to the findings of Bainbridge et al [22]. In contrast, as expected from its long elimination half-life [22], in both age groups plasma levels of amlodipine markedly increased with chronic dosing. For both dihydropyridines, plasma levels increased by 30-50% more in the older versus the young subjects, similar to the findings of previous studies [17,20].…”

Pharmacokinetics as an Aid to Optimising Compliance with Medications

“…Consistent with the first report of more prolonged action and a flatter slope of the plasma concentration-hypotensive effect curve, betaxolol treatment produced more sustained lowering of blood pressure than atenolol, even when a single daily dose was omitted. Similar comparisons among dihydropyridines, both with placebo[ 26 1 and active drug comparisons, [27] suggest that future clinical and marketing efforts will highlight the ability of a drug to maintain a therapeutic effect despite a degree of nonadherence to the prescribed dosage regimen for some formulations compared with others. This will provide an important advantage for these products because of patients' imperfect medication-taking behaviour.l 281 In effect, market forces and real world constraints will look for the proof of value of the drug.…”

Amlodipin versus Nifedipin retard Eine randomisierte Doppelblindstudie zum Vergleich der Langzeitwirksamkeit und Verträglichkeit von Amlodipin und Nifedipin retard in der Monotherapie der chronisch stabilen Angina pectoris

“…Die größere Schwankungsbreite der Plasmakonzentration von Nifedipin retard wird durch die höhere Peak-through-Ratio (definiert als Quotient der höchsten und niedrigsten Plasmakonzentration im Dosierungsintervall) reflektiert. Während die Plasmakonzentration von Amlodipin im Steady State 24 Stunden nach der letzten Einnahme immer noch 60% des Maximalwerts beträgt und somit die Peak-through-Ratio mit 1,5 gering ist [2], beträgt sie bei Nifedipin retard rund 10 [17]. Die günstigen pharmakokinetischen Eigenschaften des lang wirksamen Amlodipins ermöglichen dadurch eine gleich bleibendere Wirkung im gesamten Dosierungsintervall als Nifedipin retard.…”