Ambulatory blood pressure monitoring during sustained treatment with conventional and extended-release felodipine in mild-to-moderate hypertension

Felodipine. A review of the pharmacology and therapeutic use of the extended release formulation in cardiovascular disorders

Felodipine is a vascular-selective, dihydropyridine calcium antagonist previously investigated as a conventional tablet formulation administered twice daily. More recently considerable experience has been gained with an extended release (ER) formulation which has the convenience of once daily administration. Felodipine ER has been well studied in patients with essential hypertension. As monotherapy in mild to moderate essential hypertension, felodipine ER is at least as effective in reducing blood pressure as other calcium antagonists, beta-blockers, diuretics and ACE inhibitors, with some results favouring felodipine ER at a statistically significant level at the dosages used. It is also effective combined with controlled release metoprolol or enalapril in patients with mild to moderate essential hypertension. In patients with more severe forms of essential hypertension uncontrolled by beta-blocker and/or diuretic therapy, felodipine ER was effective as an 'add-on' therapy in placebo-controlled trials, and, at the dosages used, more effective than either sustained release nifedipine or nitrendipine. Felodipine produces effective control of blood pressure without negative effects on cardiac performance. In addition to its antihypertensive action, results suggest that felodipine therapy is associated with significant regression of left ventricular hypertrophy. Furthermore, it appears suitable for use in patients with concomitant diabetes, renal dysfunction or asthma, and is also being investigated for use in patients with congestive heart failure or angina pectoris. Felodipine ER is an effective drug for the treatment of all grades of essential hypertension, and can be used both as monotherapy and in combination with other antihypertensive agents. Further clinical experience should fully establish the long term tolerability of felodipine ER and consequently its place in therapy relative to other accepted antihypertensive drugs. However, with the convenience of once daily administration, felodipine ER is a worthwhile innovation in the treatment of hypertension.

Felodipine: a new dihydropyridine calcium-channel antagonist

Felodipine, a dihydropyridine calcium-channel antagonist, significantly reduces systolic and diastolic blood pressure (BP) in patients with hypertension and has been associated with beneficial hemodynamic effects in patients with chronic stable angina pectoris or congestive heart failure (CHF). In hypertensive patients, felodipine does not appear to significantly affect glomerular filtration rate, creatinine clearance, glucose tolerance, or plasma lipoprotein concentrations. Studies comparing felodipine with other agents as monotherapy in mild to moderate hypertension have demonstrated felodipine to be at least as efficacious as hydrochlorothiazide (HCTZ) and HCTZ plus amiloride hydrochloride in combination. Comparisons of felodipine with other agents as adjuncts to beta-blocker or diuretic therapy have shown felodipine to be at least as effective as HCTZ, propranolol hydrochloride, prazosin hydrochloride, and nifedipine. Evaluations of patients with chronic stable angina are limited, and additional studies are needed before felodipine can be recommended for the routine management of angina pectoris. Similarly, additional studies are essential to delineate the role of felodipine, if any, in the management of CHF. In the management of hypertension, felodipine 5-40 mg/d significantly reduces systolic and diastolic BP. Although some patients may be controlled throughout the entire dosing interval when felodipine is administered bid, many patients will require more frequent dosing to obtain adequate BP control. Adverse effects associated with felodipine are similar to those of other dihydropyridine calcium-channel antagonists and include peripheral edema, headache, dizziness, flushing, and fatigue. A potentially clinically important drug interaction was observed when felodipine was administered concomitantly with theophylline aminopropanol; significant decreases in theophylline concentrations were noted. In summary, felodipine appears to be safe and effective for the management of hypertension when used alone or in combination with other antihypertensive agents. The efficacy of felodipine in the management of chronic stable angina pectoris and CHF requires further investigation.

Comparison of once daily felodipine 10 mg ER and hydrochlorothiazide 25 mg in the treatment of mild to moderate hypertension

The efficacy of extended release felodipine 10 mg (ER) o.d., a new dihydropyridine calcium antagonist, and 25 mg hydrochlorothiazide (HCTZ) o.d. have been compared in a randomized, double-blind, crossover trial in 28 mildly to moderately hypertensive subjects (supine diastolic blood pressure, BP, greater than or equal to 95 mm Hg and less than or equal to 110 mm Hg on three separate occasions). Both drugs significantly reduced systolic and diastolic BP in the sitting position felodipine from 157.1/93.8 mm Hg at baseline to 133/78.9 mm Hg 2.5 h after medication and to 138/82.7 mm Hg after 2 weeks of treatment, and HCTZ from 156/95.6 mm Hg to 147/88.4 mm Hg 2.5 h after medication and to 149/89.5 mm Hg also after 2 weeks. A decrease of the same magnitude in standing systolic and diastolic BP was observed after both treatment regimens with the exception of diastolic BP 2.5 h after dosing with HCTZ, which was not significantly lower. At all times (2.5 h and 2 weeks), the reduction in systolic and diastolic BP was greater after felodipine compared to HCTZ. Heart rate was significantly increased after felodipine in both the sitting and standing positions, and both 2.5 h following medication and after 2 weeks of treatment. The difference between the regimens was significant only 2.5 h after dosing. Overall, felodipine 10 mg ER o.d. was superior to 25 mg HCTZ o.d. in lowering BP.