Generic
Amlodipine
3 brands available in the market
At a glance
Amlodipine is a dihydropyridine calcium-channel blocker used for the treatment of hypertension and angina pectoris.
Description
Amlodipine is a long-acting dihydropyridine calcium-channel blocker that influences myocardial cells, cardiac conducting system cells, and vascular smooth muscle cells. Administration results in vasodilation, reduced peripheral resistance and blood pressure, increased coronary blood flow, and reflex increase in heart rate. This leads to increased myocardial oxygen supply and cardiac output.
Indications
Essential hypertension (alone or with other antihypertensives), chronic stable angina pectoris (alone or with other antianginals), vasospastic angina (Prinzmetal's) (alone or with other antianginals).
Therapeutic class
Calcium-channel blockers
Pharmacological class
Dihydropyridine Calcium-channel Blocker
Pharmacology
Amlodipine is a dihydropyridine calcium-channel blocker with long duration of action. It inhibits transmembrane influx of calcium ions into vascular smooth muscle and cardiac muscle. Administration results in vasodilation, reduced peripheral vascular resistance, and decreased blood pressure. It increases coronary blood flow and myocardial oxygen supply.
Mechanism of action
Amlodipine inhibits transmembrane calcium ion influx into vascular smooth muscle and cardiac muscle, resulting in vasodilation. This reduces peripheral vascular resistance and blood pressure, increases coronary blood flow, and improves myocardial oxygen supply.
Dosage
Hypertension:
- Usual dose: 5 mg once daily
- Maximum dose: 10 mg once daily
- Elderly & hepatic impairment: 2.5 mg once daily (starting dose)
- When adding to other antihypertensives: 2.5 mg once daily
Angina (Chronic stable or Vasospastic):
- 5-10 mg once daily
- Elderly & hepatic impairment: Lower dose (2.5 mg)
- Most patients require: 10 mg once daily
Children (6-17 years, hypertension):
- Initial: 2.5 mg once daily
- After 4 weeks if needed: 5 mg once daily
- Doses >5 mg not studied in children
Under 6 years: Effect not known.
Administration
May be taken with or without food. Take at the same time each day. Swallow tablet whole; do not chew or crush.
Missed dose
If you miss a dose, take it as soon as you remember. If it is almost time for your next dose, skip the missed dose and continue with your regular schedule. Do not double the dose.
Side effects
Common side effects (vasodilation-related):
- Dizziness
- Flushing
- Headache
- Hypotension
- Peripheral edema
Other side effects:
- Gastrointestinal disturbances
- Increased urination frequency
- Lethargy
- Eye pain
- Mental depression
Rare side effects:
- Paradoxical increase in ischemic chest pain (at start of treatment)
- Excessive hypotension (cerebral/myocardial ischemia)
- Transient blindness
- Rash, fever, abnormal liver function
Precautions & warnings
Caution in hepatic impairment. Caution during pregnancy and breastfeeding. Angina may worsen at start of treatment; monitor closely. Avoid with beta-blockers in severe left ventricular dysfunction.
Contraindications
Hypersensitivity to dihydropyridine derivatives. Pregnancy.
Drug interactions
Digoxin: No interaction (in healthy volunteers).
Cimetidine: No interaction (in healthy volunteers).
Warfarin: No significant effect on prothrombin time.
Beta-blockers: Avoid in severe left ventricular dysfunction.
Food interactions
Food does not alter the rate or extent of amlodipine absorption.
Use in pregnancy
Pregnancy Category: C. No adequate and well-controlled studies in pregnant women. Use only if potential benefit justifies potential risk to fetus.
Pregnancy Category: C — always consult a doctor before taking during pregnancy.
Use in lactation
It is not known whether amlodipine is excreted in human milk. Discontinue nursing while amlodipine is administered.
Pediatric use
6-17 years (hypertension): 2.5 mg once daily initial; up to 5 mg once daily after 4 weeks if needed.
Under 6 years: Effect not known.
Geriatric use
Amlodipine is equally well tolerated in elderly and younger patients. Normal dosage recommended; dose increases should be done with care.
Renal / hepatic impairment
Renal impairment: Plasma concentrations not correlated with degree of impairment; normal dosage recommended. Not dialyzable.
Hepatic impairment: Mild-moderate: start at lower end of dosing range. Severe: start at 2.5 mg once daily and titrate slowly.
Overdose effects
Overdose may cause excessive peripheral vasodilation and reflex tachycardia. Severe hypotension, shock, and fatal outcomes reported. Management: cardiovascular support, vasoconstrictors, IV calcium gluconate, gastric lavage if needed. Dialysis is not effective (protein-bound).
Storage conditions
Keep out of reach of children. Store in a cool and dry place, protected from light.
Chemical structure
Amlodipine