Felodipine

Oral
Stable angina

Oral
Hypertension

Dose reduction may be necessary.

Felodipine May be taken with or without food. Avoid grapefruit juice.

Decompensated heart failure, acute MI, unstable angina pectoris, haemodynamically significant cardiac valvular obstruction, dynamic cardiac outflow obstruction. Pregnancy.

Hepatic impairment. Elderly. Lactation.

Significant: Increased angina and/or MI, peripheral oedema; mild gingival hyperplasia (particularly in patients with pronounced gingivitis or periodontitis). Rarely, symptomatic hypotension with or without syncope.
Cardiac disorders: Tachycardia, palpitations.
Gastrointestinal disorders: Nausea, abdominal pain.
General disorders and administration site conditions: Fatigue.
Nervous system disorders: Headache, dizziness, paraesthesia.
Skin and subcutaneous tissue disorders: Rash, pruritus.
Vascular disorders: Flush.

PO: C

This drug may cause headache, nausea, dizziness or fatigue, if affected, do not drive or operate machinery.

Monitor blood pressure, heart rate and ECG changes. Assess for signs and symptoms of peripheral oedema.

Symptoms: Excessive peripheral vasodilatation with marked hypotension and bradycardia. Management: Symptomatic treatment. Perform gastric lavage and administer activated charcoal. In case of severe hypotension, place the patient in supine position with the legs elevated. If insufficient, plasma volume must be increased by infusing glucose, saline or dextran. Administer IV atropine in case of bradycardia. May consider giving sympathomimetic drugs if needed.

Increased plasma concentrations with CYP3A4 inhibitors (e.g. itraconazole, ketoconazole, erythromycin, cimetidine). Decreased plasma concentrations with CYP3A4 inducers (e.g. carbamazepine, phenytoin, phenobarbital, rifampicin). May increase the plasma concentration of tacrolimus.

Increased plasma concentrations with grapefruit juice. Decreased plasma concentrations with St. John's wort. Increased rate of absorption with foods high in fat or carbohydrates.

Description:
Mechanism of Action: Felodipine is a dihydropyridine calcium channel antagonist. It suppresses calcium ions from entering the slow channels or select voltage-sensitive areas of vascular smooth muscle and myocardium during depolarisation which results in coronary vascular smooth muscle relaxation and coronary vasodilation. Additionally, it increases the delivery of myocardial oxygen in vasospastic angina.
Onset: Antihypertensive: 2-5 hours.
Duration: Antihypertensive: 24 hours.
Pharmacokinetics:
Absorption: Almost completely absorbed from the gastrointestinal tract. Foods high in fat or carbohydrates may increase the rate of absorption. Bioavailability: Approx 15%. Time to peak plasma concentration: 2.5-5 hours.
Distribution: Enters breast milk. Plasma protein binding: >99%, mainly albumin.
Metabolism: Extensively metabolised in the liver by CYP3A4 into inactive metabolites. Undergoes extensive first-pass metabolism.
Excretion: Via urine (approx 70% as metabolites); faeces (10%). Elimination half-life: 11-16 hours (immediate release).

Source: National Center for Biotechnology Information. PubChem Compound Summary for CID 3333, Felodipine. https://pubchem.ncbi.nlm.nih.gov/compound/Felodipine. Accessed Nov. 26, 2024.

Store below 25°C. Protect from light.

Anti-Anginal Drugs / Calcium Antagonists

C08CA02 - felodipine ; Belongs to the class of dihydropyridine derivative selective calcium-channel blockers with mainly vascular effects. Used in the treatment of cardiovascular diseases.

Anon. Felodipine. AHFS Clinical Drug Information [online]. Bethesda, MD. American Society of Health-System Pharmacists, Inc. https://www.ahfscdi.com. Accessed 08/10/2024.

Brayfield A, Cadart C (eds). Felodipine. Martindale: The Complete Drug Reference [online]. London. Pharmaceutical Press. https://www.medicinescomplete.com. Accessed 08/10/2024.

Clinect NZ Pty Limited. Plendil ER Modified Release Tablet data sheet 06 March 2024. Medsafe. http://www.medsafe.govt.nz. Accessed 08/10/2024.

Felodipine Tablet, Film Coated, Extended Release (Aurobindo Pharma Limited). DailyMed. Source: U.S. National Library of Medicine. https://dailymed.nlm.nih.gov/dailymed. Accessed 08/10/2024.

Felodipine Teva 5 mg Prolonged-release Tablets (Teva UK Limited). MHRA. https://products.mhra.gov.uk. Accessed 08/10/2024.

Felodipine. UpToDate Lexidrug, Lexi-Drugs Multinational Online. Waltham, MA. UpToDate, Inc. https://online.lexi.com. Accessed 08/10/2024.

Joint Formulary Committee. Felodipine. British National Formulary [online]. London. BMJ Group and Pharmaceutical Press. https://www.medicinescomplete.com. Accessed 08/10/2024.

Plendil 2.5 mg, 5 mg and 10 mg Tablets (Zuellig Pharma Sdn. Bhd.). National Pharmaceutical Regulatory Agency - Ministry of Health Malaysia. https://www.npra.gov.my. Accessed 08/10/2024.