Sildenafil

Sildenafil In Dogs & Cats: Uses, Dosage and Side Effects

Overview

• Pulmonary vasculature vasodilation, due to an increase in vascular levels of cGMP caused by inhibition of cGMP-specific phosphodiesterase type V.

Uses of Sildenafil

• Used for treating pulmonary arterial hypertension.
• Clinical studies in dogs indicate that sildenafil therapy may not significantly reduce echocardiographic measurements.
• However, patients undergoing treatment may experience improvements in their quality of life.

Dose of Sildenafil in Dogs and Cats

Dogs:

• 0.5–2.7 mg/kg p.o. q8–24h; suggested median dose from clinical studies in dogs is 3 mg/kg/day.

Cats:

• Reported dose of 1.6 mg/kg p.o. q12h tolerated and clinically efficacious.

Side Effects of Sildenafil in Dogs and Cats

• Vomiting, dizziness and raised intraocular pressure.

Contraindications of Sildenafil in Dogs and Cats

• Systemic hypotension, significant hepatic or renal impairment or bleeding disorders.

Some Notes:

• Cimetidine, erythromycin, itraconazole, and phenobarbital can elevate plasma sildenafil concentration.
• Initiation of sildenafil treatment should not coincide with an alpha-adrenergic blocker.
• Concomitant use of nitrates should be avoided, as it significantly increases the hypotensive effect of sildenafil.