What is the recommended dosage and management of Felodipine (calcium channel blocker) for hypertension?

From the Guidelines

Felodipine is typically initiated at 5 mg once daily for hypertension, with a usual maintenance dose range of 2.5-10 mg once daily. For elderly patients or those with hepatic impairment, starting at a lower dose of 2.5 mg daily is recommended. The maximum daily dose should not exceed 10 mg. Felodipine should be taken in the morning with food to reduce variability in drug absorption. Dose adjustments should be made gradually, usually at intervals of at least 2 weeks, to allow assessment of blood pressure response. As a dihydropyridine calcium channel blocker, felodipine works by blocking calcium influx into vascular smooth muscle cells, causing vasodilation and reducing peripheral resistance, thereby lowering blood pressure. Common side effects include peripheral edema, headache, flushing, and dizziness. Patients should avoid grapefruit juice while taking felodipine as it can significantly increase drug levels. Blood pressure monitoring is essential during dose titration, and patients should be advised not to discontinue the medication abruptly. Felodipine can be used as monotherapy or in combination with other antihypertensive agents such as ACE inhibitors, ARBs, or diuretics for enhanced blood pressure control, as recommended by the 2017 ACC/AHA/AAPA/ABC/ACPM/AGS/APhA/ASH/ASPC/NMA/PCNA guideline for the prevention, detection, evaluation, and management of high blood pressure in adults 1.

Some key points to consider when using felodipine include:

• The dose range and frequency of felodipine, as outlined in the guideline, with a usual dose range of 2.5-10 mg once daily 1.
• The potential for drug interactions, such as with grapefruit juice, and the need for careful monitoring of blood pressure and adjustment of the dose as needed 1.
• The use of felodipine in combination with other antihypertensive agents, such as ACE inhibitors, ARBs, or diuretics, for enhanced blood pressure control 1.
• The consideration of felodipine as a treatment option for patients with hypertension, particularly those who may not respond to or tolerate other antihypertensive agents 1.

Overall, felodipine is a useful agent for the treatment of hypertension, and its use should be guided by the latest clinical guidelines and evidence-based recommendations, such as those outlined in the 2017 ACC/AHA/AAPA/ABC/ACPM/AGS/APhA/ASH/ASPC/NMA/PCNA guideline 1.

From the FDA Drug Label

DOSAGE AND ADMINISTRATION Patients with Impaired Liver Function—Patients with impaired liver function may have elevated plasma concentrations of felodipine and may respond to lower doses of Felodipine; therefore, a starting dose of 2. 5 mg once a day is recommended.

The recommended dosage and management of Felodipine for hypertension is to start with a dose of 2.5 mg once a day, and patients should have their blood pressure monitored closely during dosage adjustment of Felodipine 2.

• The dose can be adjusted to a maximum of 10 mg once a day.
• It is essential to exercise caution when using Felodipine in patients with heart failure or compromised ventricular function, particularly in combination with a beta blocker.
• Patients should be instructed to take Felodipine whole and not to crush or chew the tablets 2.
• CYP3A4 inhibitors should be used with caution when co-administered with felodipine, as they may lead to increased plasma levels of felodipine 2.

From the Research

Dosage and Administration

• The recommended dosage of Felodipine for hypertension is 5-10 mg twice a day, with a maximum dose of 10 mg twice a day 3.
• In patients with moderate hypertension, a dose regimen of 5 mg twice a day is usually sufficient 3.
• Felodipine can be administered once or twice daily, with the extended-release formulation providing equivalent antihypertensive efficacy to the same amount of drug administered twice daily as standard tablets 4.
• In elderly hypertensive patients, felodipine 2.5 mg once daily or 5 mg once daily can be used effectively to maintain blood pressure control over 24 hours 5.

Efficacy and Safety

• Felodipine has been shown to be effective in lowering blood pressure in patients with mild to moderate hypertension, with a significant reduction in systolic and diastolic blood pressure 3, 4, 6.
• The antihypertensive effect of felodipine is dose-related, with higher doses producing greater reductions in blood pressure 3, 7.
• Felodipine is generally well-tolerated, with the most common adverse effects being ankle swelling, headache, dizziness, flushing, and fatigue 3, 4, 6.
• The overall frequency of adverse effects with felodipine appears to be similar to that of established antihypertensive drugs, although the adverse effects differ 3.

Comparison with Other Antihypertensive Agents

• Felodipine has been shown to be as effective as atenolol, hydrochlorothiazide, and other established antihypertensive agents in lowering blood pressure 4, 6.
• Felodipine has been found to have superior efficacy to hydralazine and prazosin, and is at least as effective as nifedipine, minoxidil, and propranolol, when used with diuretics and/or beta-blockers 4.
• The combination of felodipine and a beta-adrenergic blocker appears to be a good alternative to standard triple treatment, and felodipine is often effective in patients with previously "refractory" hypertension 3.