|
| Indication & Dosage |
Oral
Hypertension, Prinzmetal's angina, Stable angina
Adult: Initially, 5 mg once daily increased to 10 mg once daily if necessary.
Elderly: Initial dose: 2.5 mg once daily.
Hepatic impairment: Initial dose: 2.5 mg once daily. |
| Administration |
May be taken with or without food.
|
| Overdosage |
Overdosage may cause marked peripheral vasodilation and hypotension. |
| Contraindications |
Known hypersensitivity to dihydropyridines. |
| Special Precautions |
Impaired
liver or renal function, CHF, sick-sinus syndrome, severe ventricular
dysfunction, hypertrophic cardiomyopathy, severe aortic stenosis.
Caution when used in patients with idiopathic hypertrophic subaortic
stenosis. Elderly, children. Pregnancy, lactation. |
| Adverse Drug Reactions |
Headache,
peripheral oedema, fatigue, somnolence, nausea, abdominal pain,
flushing, dyspepsia, palpitations, dizziness. Rarely pruritus, rash,
dyspnoea, asthenia, muscle cramps.
Potentially Fatal: Hypotension, bradycardia, conductive system delay and CCF. |
| Drug Interactions |
Increased metabolism with rifampin.
Reduced hypotensive effect with calcium. Potentiates effects of
thiazide diuretics and ACE inhibitors. Avoid combination with β-blockers
in patients with markedly impaired left ventricular function. May
increase serum levels of CYP1A2 substrates e.g. aminophylline,
fluvoxamine, ropinirole. CYP3A4 inhibitors (e.g. clarithromycin,
doxycycline, isoniazid, nicardipine) may increase the effects of
amlodipine. Additive BP-lowering effects when used with sildenafil,
tadalafil or vardenafil.
Potentially Fatal: Increased metabolism with rifampin.
Reduced hypotensive effect with calcium. Potentiates effects of
thiazide diuretics and ACE inhibitors. Avoid combination with β-blockers
in patients with markedly impaired left ventricular function. May
increase serum levels of CYP1A2 substrates e.g. aminophylline,
fluvoxamine, ropinirole. CYP3A4 inhibitors (e.g. clarithromycin,
doxycycline, isoniazid, nicardipine) may increase the effects of
amlodipine. Additive BP-lowering effects when used with sildenafil,
tadalafil or vardenafil.
Click to view more amlodipine Drug Interactions
|
| Pregnancy Category (US FDA) |
Category C:
Either studies in animals have revealed adverse effects on the foetus
(teratogenic or embryocidal or other) and there are no controlled
studies in women or studies in women and animals are not available.
Drugs should be given only if the potential benefit justifies the
potential risk to the foetus.
|
| Storage |
Oral: Store at 15-30°C. |
| Mechanism of Action |
Amlodipine
relaxes peripheral and coronary vascular smooth muscle. It produces
coronary vasodilation by inhibiting the entry of Ca ions into the
voltage-sensitive channels of the vascular smooth muscle and myocardium
during depolarisation. It also increases myocardial O2 delivery in patients with vasospastic angina.
Absorption: Well absorbed from the GI tract (oral); peak plasma concentrations after 6-12 hr.
Distribution: Protein-binding: 97.5%.
Metabolism: Hepatic: Extensive.
Excretion: Via urine (mainly as metabolites, 10% as unchanged); 35-50 hr (elimination half-life). |
| MIMS Class |
Anti-Anginal Drugs / Calcium Antagonists |
| ATC Classification |
C08CA01 -
amlodipine
;
Belongs to the class of
dihydropyridine derivative selective calcium-channel blockers with
mainly vascular effects. Used in the treatment of cardiovascular
diseases.
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