Research overview: renin-angiotensin system inhibition in feline kidney disease

Inhibiting the renin-angiotensin-aldosterone system with agents such as ACE inhibitors and the angiotensin receptor blocker telmisartan has been studied to reduce proteinuria and protect the kidneys in cats with CKD, particularly those with significant protein loss. Telmisartan gained approval for reducing proteinuria in feline CKD in some regions. This overview compiles the pharmacology and trial literature rather than one source, describing how RAAS activity contributes to glomerular pressure and protein leakage, why blocking it lowers proteinuria, and the considerations around blood pressure and kidney parameters during therapy. It matters because RAAS inhibition targets a modifiable mechanism of progression, offering proteinuric cats a treatment aimed at slowing the underlying disease rather than only managing its consequences.