Oral: 5 mg, 10 mg tablets.
Action: Dihydropyridine calcium-channel blocker, with predominant action as a peripheral arteriolar vasculature, causing vasodilation and reducing afterload. Has mild negative inotropic and chronotropic effects, which are negligible at low doses.
Use: Treatment of systemic hypertension in cats and appears to be safe even when there is concurrent renal failure. Has been used in dogs for treatment of systemic hypertension and in normotensive dogs as adjunctive therapy for refractory heart failure due to mitral regurgitation. It is a very effective antihypertensive agent in cats and is frequently used in this species. It has also been shown to decrease proteinuria in cats with systemic hypertension. It is a less effective antihypertensive in dogs.
Amlodipine is metabolized in the liver and dosage should be reduced when there is hepatic dysfunction.
Safety and handling: Normal precautions should be observed.
Contraindications: Avoid in cardiogenic shock and pregnancy.
Adverse reactions: Lethargy, hypotension or inappetence are rare side effects.
Drug interactions: Hepatic metabolism may be impaired by drugs such as cimetidine. Hypotension is a risk if combined with other antihypertensives, e.g. ACE inhibitors, diuretics, beta-blockers.