Medication Considerations

Overview

Medicines play a central role in preventing and managing kidney and cardiovascular disease, but decisions about their use can become challenging during acute illness and around episodes of acute kidney injury (AKI). Many medicines that influence kidney function, blood pressure, or serum potassium are commonly paused during acute illness, yet are also disease-modifying and critically important for long-term outcomes.

AKI is most often driven by acute illness and haemodynamic disturbance rather than medication toxicity alone, and distinguishing between these mechanisms is essential for making safe prescribing decisions.

In clinically stable patients, modest rises in serum creatinine or potassium following initiation or up-titration of ACE inhibitors, ARBs, mineralocorticoid receptor antagonists (MRAs), sacubitril/valsartan, or diuretics are common and frequently expected. These changes should prompt clinical review—including assessment of volume status, blood pressure, and concurrent medicines—rather than automatic drug discontinuation. Where there is a strong prognostic indication, particularly heart failure with reduced ejection fraction or albuminuric chronic kidney disease, the harms of stopping or failing to re-start treatment often outweigh the risks associated with modest biochemical change.

This section is organised to support medicines optimisation across the AKI pathway. It begins with a practical reference table for managing medicines during AKI, followed by information on interpreting creatinine and potassium changes in clinically stable patients. It then outlines principles for re-starting and re-titrating key medicines after an episode of AKI, and concludes with the UKKA’s position on “sick day” guidance, highlighting both its intended role and its potential harms if applied too broadly. Throughout, the emphasis is on clinical judgement, careful monitoring, patient involvement, and timely re-initiation of therapy once clinically appropriate, to minimise avoidable harm and support long-term outcomes.