Medicines for Psoriatic arthritis

What it is

Psoriatic arthritis is a type of inflammatory arthritis that occurs in some people who have psoriasis, the skin condition that causes red, scaly patches. It causes inflammation in and around the joints, leading to pain, swelling and stiffness. It can affect joints in different patterns — a few large joints, many small joints, or sometimes the spine and the joints at the base of the back. Characteristic features include dactylitis, where a whole finger or toe swells up like a "sausage", and changes to the nails such as pitting or lifting. The joint symptoms may appear years after the skin psoriasis, occasionally before it, and the severity of the skin and joint problems does not always match. Left untreated, ongoing inflammation can damage the joints, which is why early recognition matters. Anyone with psoriasis who develops joint pain, swelling or stiffness should be checked for it.

How it is treated

The aim is to control inflammation, relieve symptoms and — importantly — treat early to prevent lasting joint damage. For milder or localised symptoms, NSAIDs can ease pain and stiffness. Where the arthritis is more persistent or is affecting several joints, disease-modifying medicines such as methotrexate (and other DMARDs) are used to dampen the underlying inflammation and protect the joints. For disease that remains active despite these, or that is causing joint erosion, biologic medicines — anti-TNF biologics and IL (interleukin) biologics — are highly effective and can also help the skin psoriasis. Methotrexate and biologics need monitoring, and biologics require screening for infection, including tuberculosis, before starting. Care is often shared between rheumatology and dermatology, treating both joints and skin together.