Home Drug Guide Felodipine

Drug Guide

Generic Name

Felodipine

Brand Names Plendil

Classification

Therapeutic: Antihypertensive

Pharmacological: Calcium channel blocker (dihydropyridine)

FDA Approved Indications

  • Hypertension

Mechanism of Action

Felodipine inhibits calcium ion influx across excitable membranes, primarily in vascular smooth muscle, leading to vasodilation and decreased blood pressure.

Dosage and Administration

Adult: Initial dose of 5 mg once daily, may be titrated up to 10 mg once daily based on response.

Pediatric: Not approved for pediatric use.

Geriatric: Start at lower end of dosing range due to increased sensitivity and comorbidities.

Renal Impairment: Use with caution; no specific dosage adjustment provided.

Hepatic Impairment: Use with caution; start at lower dose due to impaired metabolism.

Pharmacokinetics

Absorption: Well absorbed from gastrointestinal tract; extensive first-pass metabolism.

Distribution: Widely distributed; protein binding approximately 99%.

Metabolism: Primarily hepatic via CYP3A4.

Excretion: Biliary and renal pathways; largely excreted as metabolites.

Half Life: About 24 hours, allowing once-daily dosing.

Contraindications

  • Hypersensitivity to felodipine or other dihydropyridines.
  • Severe aortic stenosis.

Precautions

  • Use with caution in patients with hepatic impairment, have heart failure, or unstable angina.

Adverse Reactions - Common

  • Headache (Common)
  • Dizziness (Common)
  • Flushing (Common)
  • Peripheral edema (Common)

Adverse Reactions - Serious

  • Arrhythmias (Rare)
  • Allergic reactions (rash, angioedema) (Rare)

Drug-Drug Interactions

  • Intensive CYP3A4 inhibitors (e.g., ketoconazole, azole antifungals) may increase felodipine levels.
  • CYP3A4 inducers (e.g., rifampin) may decrease its effectiveness.

Drug-Food Interactions

  • Grapefruit juice (may increase plasma levels).

Drug-Herb Interactions

N/A

Nursing Implications

Assessment: Monitor blood pressure and heart rate regularly during therapy. Assess for signs of hypotension.

Diagnoses:

  • Risk for hypotension
  • Ineffective tissue perfusion

Implementation: Administer orally, preferably in the morning. Observe for signs of excessive hypotension.

Evaluation: Assess blood pressure and symptom control regularly to determine therapeutic effectiveness.

Patient/Family Teaching

  • Take medication exactly as prescribed.
  • Avoid grapefruit juice during therapy.
  • Report any signs of swelling, dizziness, or chest pain.
  • Do not stop medication abruptly.

Special Considerations

Black Box Warnings:

  • None currently for felodipine.

Genetic Factors: Genetic variations in CYP3A4 may affect metabolism.

Lab Test Interference: May cause false low readings of serum digoxin.

Overdose Management

Signs/Symptoms: Severe hypotension, tachycardia or bradycardia, dizziness, syncope.

Treatment: Supportive care, intravenous fluids, vasopressors if necessary, and calcium infusion as an antidote in severe cases.

Storage and Handling

Storage: Store at room temperature away from moisture and heat.

Stability: Stable for 2 years when stored properly.

🛡️ 5 Critical Medication Safety Tips for Nurses

1

Triple-Check High-Risk Medications

Always have another nurse verify insulin, heparin, warfarin, and chemotherapy drugs. These "high-alert" medications cause the most serious errors. Check concentration, dose calculation, and pump settings twice.

2

Know Look-Alike, Sound-Alike Drugs

Common mix-ups: hydromorphone/morphine, Celebrex/Celexa, Zyprexa/Zyrtec. Always use BOTH generic and brand names, read labels twice, and use barcode scanning when available. One wrong letter can be fatal.

3

Assess Before AND After Giving Meds

Check vitals before cardiac meds, pain levels before analgesics, and blood glucose before insulin. Always reassess within 30 minutes to evaluate effectiveness and watch for adverse reactions.

4

Watch for Drug Interactions

Common dangerous combinations: warfarin + aspirin (bleeding), ACE inhibitors + potassium (hyperkalemia), digoxin + diuretics (toxicity). Always check drug interactions before administering new medications.

5

Educate Your Patients

Teach patients medication names, purposes, major side effects, and what to report. Informed patients catch errors and improve compliance. Always encourage questions - an educated patient is a safer patient.

⚡ Remember: When in doubt, don't give it out! It's always safer to double-check than regret later.

⚠️ Medical Disclaimer

This drug guide is for educational purposes only and is NOT intended for clinical use. Always consult current prescribing information, healthcare providers, and institutional protocols before administering any medication. Do not use this information for patient care decisions.