Felodipine: Uses, Dosage, Side Effects, and Safe Tips

Felodipine is a prescription calcium channel blocker (CCB) used to treat high blood pressure (hypertension). Lowering blood pressure helps protect your heart, brain, kidneys, and blood vessels. Felodipine comes as extended-release (ER) tablets taken once daily.

Educational disclaimer: This article is for general information only and isn’t medical advice. Always follow your clinician’s instructions and the Medication Guide for your specific product.

What Is Felodipine?

Felodipine belongs to the dihydropyridine class of CCBs (same family as amlodipine and nifedipine). These medicines relax blood vessels so the heart pumps more easily.

Formulations & strengths (modified/extended release):

• 2.5 mg, 5 mg, 10 mg ER tablets
• Designed for once-daily dosing. Do not crush, split, or chew.

How Does Felodipine Work?

Felodipine blocks L-type calcium channels in vascular smooth muscle, which:

• Dilates arteries and lowers systemic vascular resistance
• Reduces blood pressure at rest and during activity
• May ease Raynaud’s phenomenon in select patients (off-label, clinician-directed)

Heart rate can rise slightly at first (reflex tachycardia) but typically settles as blood pressure improves.

Common Uses

• Primary use: Treatment of hypertension in adults (alone or combined with other agents such as ACE inhibitors, ARBs, or thiazide diuretics)
• Sometimes used (clinician-directed/off-label): Raynaud’s phenomenon

Not for emergency treatment of very high blood pressure or chest pain. Keep using other prescribed heart medicines unless your clinician tells you to change them.

Dosage & Administration

Your exact plan depends on age, other conditions, and medicines. Always use the lowest effective dose.

Typical adult dosing

• Start:5 mg once daily
  • Some patients—older adults, those with liver impairment, or those prone to low blood pressure—may start at 2.5 mg once daily.
• Titration: Recheck BP in 1–2 weeks; your clinician may adjust by 2.5–5 mg increments.
• Usual range: 2.5–10 mg once daily (some labels allow higher under specialist care).
• Max is product/region specific—follow your label and prescriber.

How to take it (step-by-step)

1. Same time each day, with a light meal or without food—be consistent.
2. Swallow whole with water. Do not crush or split extended-release tablets.
3. Avoid grapefruit or grapefruit juice (see interactions).
4. If you miss a dose, take it the same day when remembered. Skip if it’s close to the next dose—don’t double.

Special populations

• Liver impairment: Often start at 2.5 mg; monitor closely.
• Kidney impairment: Usually no change, but BP/side effects still require monitoring.
• Children: Safety and efficacy not established.

Side Effects

Common (often improve over time):

• Ankle/foot swelling (peripheral edema)
• Headache, flushing, warmth, dizziness
• Fatigue or palpitations

Less common but important—contact your clinician:

• Low blood pressure (fainting, lightheadedness)
• Worsening chest pain shortly after starting or increasing the dose
• Gingival overgrowth (gum swelling or bleeding—see dental tips below)
• Allergic reactions (rash, swelling, trouble breathing—seek emergency care)

Dental health tip: Good toothbrushing/flossing and regular dental cleanings help prevent gingival hyperplasia sometimes linked with dihydropyridine CCBs.

Warnings & Precautions

• Severe aortic stenosis or unstable angina: Use with caution; specialist guidance required.
• Heart failure: Dihydropyridines can cause edema; clinicians weigh risks/benefits and often combine with other BP agents.
• Liver disease: You may need lower doses and closer monitoring.
• Pregnancy & breastfeeding: Discuss risks/benefits with your clinician before use.
• Driving/activities: Until you know your response, be careful with tasks requiring alertness.

Drug & Food Interactions

• Grapefruit / grapefruit juice: Avoid. It inhibits CYP3A4 and can raise felodipine levels, increasing side-effect risk.
• Strong CYP3A4 inhibitors (e.g., clarithromycin, erythromycin, ketoconazole/itraconazole, HIV protease inhibitors) can raise levels—dose changes or alternatives may be needed.
• CYP3A4 inducers (e.g., rifampin, carbamazepine, phenytoin, St. John’s wort) can lower effectiveness.
• Other BP meds (ACEIs/ARBs, diuretics, beta-blockers): Often used together—your clinician will adjust to avoid too-low BP.
• Alcohol: Can enhance BP-lowering effects—use cautiously.

Always provide a full list of prescriptions, OTC medicines, and supplements to your pharmacist/clinician.

Felodipine vs. Other Options

• Felodipine vs amlodipine: Both are once-daily dihydropyridine CCBs. Amlodipine has very long half-life and is more commonly used; felodipine is a useful alternative if amlodipine isn’t tolerated or if a specific response is desired.
• Compared with ACEI/ARB or thiazide: Choice depends on age, race/ethnicity, kidney function, co-conditions (diabetes, CKD), and guideline strategy. Many patients need two or more medications for best control.

Cost & Access

• Available as generic felodipine ER (often affordable). Prices vary by pharmacy and dose. Ask about discount programs or insurance coverage.

Special Section: 2.5 mg vs 5 mg vs 10 mg (ER Tablets)

• 2.5 mg: Typical starting dose for older adults or those sensitive to BP drops.
• 5 mg: Standard start for many adults.
• 10 mg: Used if BP remains above goal after titration and well-tolerated.
• Because tablets are extended-release, don’t split—dose adjustments are made by switching tablet strengths.

Proper Care While on Felodipine

• Check BP at home. Keep a log (morning/evening) to share at visits.
• Limit salt, stay active, and aim for a healthy weight—these changes boost medication results.
• Call promptly for persistent swelling, severe dizziness, or new/worsening chest pain.
• Dental care: Brush and floss daily; schedule dental cleanings to minimize gum overgrowth.

FAQs (12 Quick Answers)

1. What is felodipine used for?
   To lower high blood pressure; sometimes for Raynaud’s as directed.
2. How fast does it work?
   BP improvement begins within hours; full effect after 1–2 weeks of steady dosing.
3. What’s the usual starting dose?
   5 mg once daily (or 2.5 mg in older adults or those with liver impairment).
4. Can I crush the tablet?
   No. It’s extended-release—swallow whole.
5. What foods should I avoid?
   Grapefruit and grapefruit juice.
6. Why are my ankles swollen?
   Peripheral edema is a common, usually dose-related effect; call your clinician if bothersome.
7. Is it safe with other BP drugs?
   Often yes—felodipine is commonly combined with ACEIs/ARBs or diuretics.
8. What if I feel dizzy after a dose?
   Sit or lie down; rise slowly. If symptoms persist, contact your clinician—your dose may need adjustment.
9. Can I drink alcohol?
   Alcohol can amplify BP-lowering; moderate or avoid based on your clinician’s advice.
10. Does felodipine affect the heart rate?
    A mild increase can occur initially. Report palpitations or chest pain.
11. Is it okay during pregnancy or breastfeeding?
    Discuss with your clinician; data are limited and choices are individualized.
12. What if I miss a dose?
    Take it the same day when remembered; skip if close to the next dose—don’t double.

Final Thoughts (Best-Practice Summary)

• Felodipine ER is a once-daily, effective option for blood pressure control.
• Start low and titrate, monitor home BPs, and keep regular check-ins.
• Avoid grapefruit, watch for ankle swelling or dizziness, and keep up with dental care.
• Combine medication with lifestyle changes for the best long-term heart and kidney protection.