Medicines for Adult-onset Still's disease

What it is

Adult-onset Still's disease (AOSD) is a rare inflammatory condition that causes a characteristic combination of symptoms: high, spiking fevers (often occurring once or twice a day, typically in the evening, with the temperature returning to normal in between), a distinctive salmon-pink or discoloured rash that often comes and goes with the fevers, and joint pain and swelling (arthritis), along with muscle aches, a sore throat, and general symptoms such as tiredness. It is an 'autoinflammatory' condition, meaning it involves the inflammatory part of the immune system being overactive, though the exact cause is not known. Because its symptoms — particularly the fevers — can mimic infections and other conditions, and there is no single definitive test, adult-onset Still's disease is often diagnosed after other causes (such as infections and cancers) have been excluded, along with recognising the typical pattern and finding certain blood test changes (such as markedly raised inflammation and a very high level of a protein called ferritin). It can vary in course — some people have a single episode that resolves, others have recurring flares, and some have a more persistent form with ongoing arthritis. It is managed by specialists, and treatment can control the inflammation well.

How it is treated

Adult-onset Still's disease is managed by specialists (usually rheumatologists), and because it can mimic other conditions, an important early step is excluding infections, cancers and other causes, alongside recognising the typical features. Treatment aims to control the inflammation and relieve the fevers, rash and joint symptoms, and is tailored to the severity and course. For milder disease, anti-inflammatory medicines may help. For more significant disease, steroids are commonly used to bring the inflammation under control, often alongside other medicines that calm the immune system (disease-modifying medicines) to control the disease and allow the steroid dose to be reduced over time. For more resistant or severe disease, targeted biologic medicines that block specific inflammatory signals are often very effective and are increasingly used. Managing any complications, and monitoring the disease and treatment over time, are part of care. Because the course varies, treatment is individualised — some people are able to reduce or stop treatment after a single episode settles, while others need longer-term treatment for recurring or persistent disease. The reassuring message is that adult-onset Still's disease, though rare and sometimes difficult to diagnose, is treatable — medicines that calm the immune and inflammatory response can control the fevers, rash and joint symptoms well, and specialist care guides management.