Renin–angiotensin system inhibitors (RASi) are not nephrotoxic – they protect the kidneys and the heart

Healthcare professionals should not label medications as 'kidney toxins' unless this is actually the case, especially medications that instead confer clear prognostic benefit, such as renin-angiotensin system inhibitors (RASi). This is imperative when discussing treatments with people with long-term health conditions, for whom RASi significantly reduce death, progression of chronic kidney disease (CKD) and hospitalisation. RASi are fundamental to management of heart failure with reduced ejection fraction (HFrEF) and CKD with proteinuria, yet are frequently called 'nephrotoxic'. The association between RASi use and acute kidney injury (AKI) is too often mistaken for 'causation'; it is largely driven by the use of RASi to treat long-term conditions that increase AKI risk, such as HFrEF, CKD and diabetes mellitus. Mislabelling RASi as 'nephrotoxic' adversely affects vital decision making, driving a tendency for RASi avoidance, even when RASi use has clear prognostic benefit. Healthcare education must embed this clinically important change to convention.