Uses/Indications: Treatment of hypertension (HTN) in felines (systolic blood pressure > 160mm Hg), which is typically secondary to other diseases (renal failure, cardiac causes, such as thyrotoxic cardiomyopathy or primary hypertrophic cardiomyopathy, etc.) and is most often seen in middle-aged or geriatric cats. These cats typically present with acute symptoms such as blindness, seizures, collapse, and paresis.
Studies: 1. In a retrospective study, medical records from 69 cats with systemic HTN and HTN retinopathy were reviewed. 68.1% of the cats were referred because of vision loss; retinal detachment, hemorrhage, edema, and degeneration. Amlodipine decreased BP in 31 of 32 cats and improved ocular signs in 18 of 26 cats.
2. Researchers at the University of Wisconsin-Madison, administered Amlodipine at an oral daily dosage of 0.625mg per cat. Average indirect systolic blood pressure measurements in those 12 cases decreased significantly from 198 to 155mm Hg during amlodipine treatment.
Adverse Effects: hypotension, azotemia, lethargy, hypokalemia, reflex tachycardia, and weight loss
Dosing: 0.625mg PO Daily; some larger cats (>4kg) or those with severe hypertension may require doses as high as 1.25mg PO BID. When used topically, start with an initial dose of 0.625mg topically QD and titrate dose after 1 week of treatment.
Monitoring Parameters: Blood Pressure, Ophthalmic exam, Adverse Effects