Medicines for Acute kidney injury

What it is

Acute kidney injury (AKI) is a sudden reduction in how well the kidneys are working, which happens over hours to days. It is common, particularly in people who are unwell for another reason, and unlike chronic kidney disease (which develops slowly over years), AKI comes on quickly and is often reversible if the cause is treated promptly. The kidneys filter waste and excess fluid from the blood, balance the body’s salts and water, and help control blood pressure, so when they suddenly work less well, waste products and fluid can build up and the body’s balance is disturbed. AKI is usually triggered by another problem rather than a disease of the kidneys themselves — common causes include dehydration (from not drinking enough, or from illnesses causing vomiting or diarrhoea), serious infection (sepsis), a drop in blood flow to the kidneys (for example from a serious illness), certain medicines (which can affect the kidneys, particularly during illness or dehydration), and blockages to the flow of urine. People at higher risk include older people, those with existing kidney disease or other long-term conditions, and those taking certain medicines. AKI is often detected on blood tests (which show rising levels of waste products) rather than through obvious symptoms; when symptoms do occur, they can include passing less urine than usual, feeling sick, tiredness, confusion, and swelling. Because AKI is often reversible if recognised and treated early — by addressing the cause, restoring fluids, and stopping or adjusting medicines that can harm the kidneys — prompt recognition matters, and in severe cases temporary support for the kidneys (dialysis) may be needed. Preventing AKI, particularly during illness, is also important.

How it is treated

Acute kidney injury is managed by treating the underlying cause and supporting the kidneys while they recover, and because it is often reversible when recognised early, prompt action is important. Management usually involves: identifying and treating the cause — for example, giving fluids to treat dehydration or restore blood flow to the kidneys, treating any infection, and relieving any blockage to the flow of urine; reviewing and, where needed, temporarily stopping or adjusting medicines that can affect the kidneys or that may build up when the kidneys are not working well; and monitoring kidney function, fluid balance, and the body’s salts with blood tests, correcting any imbalances. Most people recover kidney function when the cause is treated. In more severe cases, temporary treatment to do the kidneys’ job — dialysis (filtering the blood by machine) — may be needed for a period while the kidneys recover. Care is often given in hospital, particularly when AKI occurs alongside another serious illness. Prevention is an important part of the picture, especially for people at higher risk: staying well hydrated (particularly during illnesses that cause vomiting or diarrhoea, or in hot weather), and being aware that during such illnesses some regular medicines may need to be temporarily paused on medical advice ("sick day" guidance for certain medicines), can help prevent AKI. Because AKI is often picked up on blood tests during other illness, and because early treatment improves recovery, awareness among people at higher risk and prompt medical care during illness are valuable. The reassuring message is that acute kidney injury is often reversible when recognised and treated early — by addressing the cause, restoring fluids, and adjusting medicines — while severe cases may need temporary dialysis, and prevention (especially staying hydrated during illness) is important for those at risk.