Complications of gout can include small lumps forming under the skin (tophi), joint damage, kidney stones and pain that could affect your daily life.

Tophi

Crystals of sodium urate often form in tissues both outside and inside the joint. The crystals that build up under the skin may form small white or yellow lumps known as subcutaneous tophi.

Tophi are usually painless, but they can form in awkward places, such as at the ends of your fingers and around your toes. It usually takes several years after the first attack of gout for tophi to develop, but some people develop tophi even before experiencing an acute attack. 

They usually form on toes, heels, knees, fingers, forearms and elbows, but can occur anywhere in the body, even in the spinal canal or vocal chords (though this is rare).

If there are tophi below the skin, there will be more within the cartilage and bone of your joints.  

They are usually taken as a sign of severe gout and a reason to start uric acid lowering therapy, such as the medication allopurinol. Read more about the treatment of gout.

Successful lowering of the uric acid to below the saturation point for urate crystal formation will prevent the tophi from getting any bigger, and allow them to slowly reduce in size as the crystals dissolve. 

Occasionally, tophi can become inflamed and even produce a discharge consisting of a mixture of pus and a white, toothpaste-like material (urate crystals).

If you have tophi that are large or painful, you may have difficulty doing everyday tasks such as preparing food or dressing yourself.

Speak to your GP if you have tophi and difficulty performing everyday tasks. Your GP can give advice on how to make these activities easier. If you have very large or painful tophi, they may have to be surgically removed.

Joint damage

If urate crystals continue to build up and form hard lumps (tophi) within the cartilage and bone of the joints, this could lead to permanent damage.

If you don't treat gout by reducing uric acid levels to below saturation point, future attacks may become more frequent and prolonged, and your likelihood of developing permanent joint damage will be increased.

In the most serious cases, surgery may be required to repair or replace a damaged joint.

Kidney stones

Occasionally, high levels of uric acid can lead to formation of uric acid crystals in your urinary tract, resulting in kidney stones. High uric acid levels can also lead to calcium stones forming.

Around 10-25% of people with gout develop kidney stones. Some kidney stones interfere with the flow of urine, resulting in pain when you pass urine, and can make you feel that you need to pass urine more often.

Kidney stones can also cause an infection in your urinary system.

Most kidney stones are small and pass through your system naturally, usually within a day or two. Drink plenty of water as this will help flush the stones naturally.

You may be prescribed medication to make your urine less acidic, which should help dissolve any kidney stones that may have developed.

Psychological effects

As well as affecting you physically, gout can also affect your mood, work and home life. The severe pain that gout causes can make it difficult to get around, which can sometimes lead to feelings of depression or anxiety.

Your GP will discuss ways to make your day-to-day life easier during a gout attack. They can also help you deal with any feelings of depression you may experience.

Read more advice about living with pain.

Joint

Joints are the connection point between two bones that allow movement.

Kidney

Kidneys are a pair of bean-shaped organs located at the back of the abdomen, which remove waste and extra fluid from the blood and pass them out of the body as urine.