Amlodipine

# Amlodipine ## Overview - **Classification**: Dihydropyridine Calcium Channel Blocker (DHP-CCB) - **Mechanism**: Inhibits calcium influx into vascular smooth muscle and myocardial cells, leading to peripheral arterial vasodilation and reduced cardiac afterload. ## Primary Indications 1. **Hypertension**: Management of essential hypertension. 2. **Coronary Artery Disease**: Symptomatic chronic stable angina and vasospastic (Prinzmetal's) angina. ## Adult Dosing ### Standard Dosing **Hypertension & Angina** - **Dose**: Initially **5 mg** - **Frequency**: Once daily (QD) - **Route**: Oral (PO) - **Maximum Dose**: **10 mg** QD - **Special Considerations**: May increase dose after 7-14 days based on clinical response. ### Dose Adjustments - **Renal Impairment**: No dose adjustment required. - **Hepatic Impairment**: Start with **2.5 mg** QD. Titrate slowly. - **Elderly Patients**: Consider starting with **2.5 mg** QD. Titrate slowly. ## Pediatric Dosing ### Neonates (0-28 days) - **Not Recommended**: Safety and efficacy not established. ### Infants (1-12 months) - **Not Recommended**: Safety and efficacy not established. ### Children (6-17 years) **Hypertension** - **Dose**: Initially **2.5 mg** - **Frequency**: Once daily (QD) - **Route**: Oral (PO) - **Maximum Dose**: **5 mg** QD - **Special Notes**: Doses above 5 mg daily have not been studied in pediatric patients. ### Adolescents (13-18 years) **Hypertension** - **Dose**: Follow Children's (6-17 years) dosing initially. - **Maximum**: **5 mg** QD. Some guidelines suggest adult doses (up to 10 mg) if needed and tolerated, but **5 mg** is the studied maximum for this age group. ## Safety Information ### Contraindications - **Absolute**: Hypersensitivity to amlodipine or other dihydropyridine calcium channel blockers. - **Relative**: Severe aortic stenosis, cardiogenic shock (caution). ### Common Adverse Effects - **Very Common (>10%)**: Peripheral edema, headache, fatigue. - **Common (1-10%)**: Dizziness, palpitations, flushing, abdominal pain, nausea. - **Serious but Rare**: Myocardial infarction, arrhythmia, angioedema. ### Key Drug Interactions - **CYP3A4 Inhibitors (e.g., ketoconazole, clarithromycin)**: May increase amlodipine exposure. Monitor for hypotension/edema, consider dose reduction. - **CYP3A4 Inducers (e.g., rifampin)**: May decrease amlodipine exposure. Monitor for decreased efficacy. - **Simvastatin**: Amlodipine may increase simvastatin exposure. Limit simvastatin to **20 mg/day**. ## Monitoring & Follow-up - **Before Treatment**: Obtain baseline blood pressure (BP) and heart rate. - **During Treatment**: Monitor BP regularly (e.g., weekly after dose adjustments, then monthly/quarterly). - **Clinical Signs**: Monitor for peripheral edema, headache, dizziness, and signs of excessive hypotension. ## Clinical Pearls - 💡 **Timing**: Can be taken with or without food. Consistent daily timing is helpful. - 💡 **Edema**: Peripheral edema is dose-dependent and not typically relieved by diuretics. - 💡 **Titration**: Allow **7-14 days** between dose increases to assess full clinical effect. - 💡 **Compliance**: Once-daily dosing aids adherence. > **⚠️ Important**: This information is for educational purposes only. Always consult current prescribing information, local guidelines, and clinical judgment before prescribing.