Treatment of canine pulmonary arterial hypertension: is tadalafil an appropriate alternative to sildenafil?

The drugs tadalafil and sildenafil share the same mechanism. Although more research is necessary to solidify the recommendation of the routine use of tadalafil, human and dog data combined with pharmacokinetic data suggest that dogs may be safely treated for canine pulmonary arterial hypertension with tadalafil for the convenience of less frequent dosing, with effects similar to sildenafil. While more costly, the use of tadalafil has positive implications in improving compliance and, therefore, therapeutic outcomes in canine pulmonary arterial hypertension. This article explores the data for the use of tadalafil in canine pulmonary arterial hypertension and provides example compounded preparations.