Felodipine

Felodipine extended-release tablets, USP are indicated for the treatment of hypertension, to lower blood pressure. Lowering blood pressure lowers the risk of fatal and non-fatal cardiovascular events, primarily strokes and myocardial infarctions. These benefits have been seen in controlled trials of antihypertensive drugs from a wide variety of pharmacologic classes including felodipine. Control of high blood pressure should be part of comprehensive cardiovascular risk management, including, as appropriate, lipid control, diabetes management, antithrombotic therapy, smoking cessation, exercise, and limited sodium intake. …

• The recommended starting dose is 5 mg once a day
• Depending on the patient's response, the dosage can be decreased to 2.5 mg or increased to 10 mg once a day
• These adjustments should occur generally at intervals of not less than 2 weeks
• The recommended dosage range is 2.5 to 10 mg once daily
• In clinical trials, doses above 10 mg daily showed an increased blood pressure response but a large increase in the rate of peripheral edema and other vasodilatory adverse events (see ADVERSE REACTIONS )
• Modification of the recommended dosage is usually not required in patients with renal impairment
• Felodipine extended-release tablets, USP should regularly be taken either without food or with a light meal (see CLINICAL PHARMACOLOGY, Pharmacokinetics and Metabolism )
• Felodipine extended-release tablets, USP should be swallowed whole and not crushed or chewed
• Geriatric Use Patients over 65 years of age are likely to develop higher plasma concentrations of felodipine (see CLINICAL PHARMACOLOGY )
• In general, dose selection for an elderly patient should be cautious, usually starting at the low end of the dosing range (2.5 mg daily)
• Elderly patients should have their blood pressure closely monitored during any dosage adjustment. …

• Safety and effectiveness
• In pediatric patients have not been established

Plasma concentrations of felodipine, after a single dose and at steady-state, increase with age. Mean clearance of felodipine in elderly hypertensives (mean age 74) was only 45% of that of young volunteers (mean age 26). At steady-state mean AUC for young patients was 39% of that for the elderly. Data for intermediate age ranges suggest that the AUCs fall between the extremes of the young and the elderly. …

• Patients should be instructed to take felodipine extended-release tablet, USP whole and not to crush or chew the tablets
• They should be told that mild gingival hyperplasia (gum swelling) has been reported
• Good dental hygiene decreases its incidence and severity
• NOTE: As with many other drugs, certain advice to patients being treated with felodipine extended-release is warranted
• This information is intended to aid in the safe and effective use of this medication
• It is not a disclosure of all possible adverse or intended effects

Felodipine extended-release tablets, USP are contraindicated in patients who are hypersensitive to this product.

CYP3A4 Inhibitors Felodipine is metabolized by CYP3A4. Co-administration of CYP3A4 inhibitors (e.g., ketoconazole, itraconazole, erythromycin, grapefruit juice, cimetidine) with felodipine may lead to several-fold increases in the plasma levels of felodipine, either due to an increase in bioavailability or due to a decrease in metabolism. These increases in concentration may lead to increased effects, (lower blood pressure and increased heart rate). These effects have been observed with co-administration of itraconazole (a potent CYP3A4 inhibitor). Caution should be used when CYP3A4 inhibitors are co-administered with felodipine. A conservative approach to dosing felodipine should be taken. …

PRECAUTIONS General Hypotension Felodipine, like other calcium antagonists, may occasionally precipitate significant hypotension and, rarely, syncope. It may lead to reflex tachycardia which in susceptible individuals may precipitate angina pectoris (see ADVERSE REACTIONS ). Heart Failure Although acute hemodynamic studies in a small number of patients with NYHA Class II or III heart failure treated with felodipine have not demonstrated negative inotropic effects, safety in patients with heart failure has not been established. …

In controlled studies in the United States and overseas, approximately 3000 patients were treated with felodipine as either the extended-release or the immediate-release formulation. The most common clinical adverse events reported with felodipine extended-release administered as monotherapy at the recommended dosage range of 2.5 mg to 10 mg once a day were peripheral edema and headache. Peripheral edema was generally mild, but it was age and dose related and resulted in discontinuation of therapy in about 3% of the enrolled patients. …

Pregnancy Pregnancy Category C Teratogenic Effects Studies in pregnant rabbits administered doses of 0.46, 1.2, 2.3 and 4.6 mg/kg/day (from 0.8 to 8 times 1 the maximum recommended human dose on a mg/m 2 basis) showed digital anomalies consisting of reduction in size and degree of ossification of the terminal phalanges in the fetuses. The frequency and severity of the changes appeared dose related and were noted even at the lowest dose. …

Oral doses of 240 mg/kg and 264 mg/kg in male and female mice, respectively, and 2390 mg/kg and 2250 mg/kg in male and female rats, respectively, caused significant lethality. In a suicide attempt, one patient took 150 mg felodipine together with 15 tablets each of atenolol and spironolactone and 20 tablets of nitrazepam. The patient's blood pressure and heart rate were normal on admission to hospital; he subsequently recovered without significant sequelae. Overdosage might be expected to cause excessive peripheral vasodilation with marked hypotension and possibly bradycardia. …

Take it when you remember, unless it is nearly time for the next dose. Then skip the missed one. Never take two doses at once to make up for it. Check your leaflet, as some medicines are different.