People often find that when they start to take allopurinol, that they can get an attack of gout. The reason that this happens is because crystals of uric acid are normally found tightly packed within the cartilage that lines the bones, and when they start taking allopurinol, their uric acid is lowered so the crystals start to dissolve and start to become smaller meaning that they can be more easily shaken loose into the joint, which is when that leads to inflammation and to an attack of gout. So although people often see having an attack of gout after starting allopurinol as a side effect of allopurinol, and clearly that’s something that from the patient’s point of view is unwanted, we should actually be seeing attacks like that as a sign of successful treatment a sign that treatment is working because it is telling us that uric acid levels are starting to be lowered, and that crystals are starting to dissolve. This also explains why people can continue to have attacks of gout for up to two years after starting allopurinol, because it takes up to two years for the crystals to dissolve completely.

It sometimes causes confusion that when uric acid levels are measured during an attack of gout, they can come back as low or normal. The reason for this is that, at times when theres a lot of inflammation around in the body such as during an attack of gout the kidneys actually pass more uric acid out into the urine, which means that the level in the blood drops. So the most important message from this is that if somebody is thought to have gout, but they are found to have a low or normal uric acid level during an attack of gout, the blood test should be repeated when the attack has settled down.

Gout is usually treated in two phases; the first phase is the treatment of the attack itself, and then the second phase relates to longer term management. The aim of treating an acute attack of gout is to provide rapid relief from the very intense pain and inflammation which people get. And the most commonly used drugs to do this are either anti-inflammatory drugs, or colchicine. And these drugs are usually taken until the pain and inflammation have settled down.

Long-term treatment of gout aims to reduce uric acid levels. The reason for this is that we know that if we can reduce uric acid levels, we can stop acute attacks of gout from happening. We can prevent joint damage from happening in the long term, and we can also cause tophi – which are the deposits of uric acid sometimes found under the skin – we can cause those to shrink and eventually go away. If gout is only treated by treating symptoms that occur during the attack of gout, then we don’t get rid of the crystals and hence those crystals can still go on to cause long term problems.

Long-term treatment of gout aims to reduce uric acid levels; the reason for this is that we know that if we can reduce uric acid levels we can stop acute attacks of gout from happening, we can prevent joint damage from happening in the long term, and we can also cause tophi – which are the deposits of uric acid sometimes found under the skin – we can cause those to shrink and eventually go away. If gout is only treated by treating symptoms that occur during the attack of gout, then we don’t get rid of the crystals and hence those crystals can still go on to cause long term problems.

Reducing uric acid levels in the long term is best achieved by a combination of things that people can do for themselves, and drug treatment. Some people do get gout because they’re overweight, or because they drink too much alcohol, particularly beer, or because they eat too much of certain types of food, such as red meat or seafood. And so for those people reducing those things might help, but for most people who have gout that doesn’t have any effect. And in fact, unfortunately, we know that for most people with gout we don’t lower their uric acid level enough without drug treatment. The most commonly used treatment for gout in the long term is allopurinol, and allopurinol is a very safe treatment, which doesn’t cause many people to have health-related problems.

Gout is the most common cause of inflamed joints, and affects about 1.4% of people in the UK. People get gout because they have too much of a substance called uric acid in their blood. We all have uric acid in our blood, it’s just that people with gout have more uric acid than other people and what happens is that, as uric acid levels rise and saturate body tissues with uric acid, then little crystals, tiny crystals of uric acid, form in and around joints which leads to symptoms of gout.

Well we don’t know for sure why gout most commonly affects the big toe, although there are a number of theories. So the first possible explanation is that the foot is cooler than other parts of the body, and crystals of uric acid find it more easy to form at lower temperatures.

The second theory relates to the fact that people quite commonly stub their toe or knock their foot, and that this can commonly lead to an attack of gout.

The third possible explanation relates to other types of arthritis, and the big toe is a joint that is very commonly affected by osteoarthritis, and it’s thought that uric acid crystals form more easily inside joints where the cartilage is affected by arthritis. In truth, we don’t know which of these reasons is the cause, and it’s possible that all three reasons are playing together to explain why gout commonly affects the big toe.

Well typically people will have high uric acid levels for a variable period of time which may be up to several years or even decades, and during this time they may well not know that theres anything wrong with them. Then out of the blue, all of a sudden, somebody will experience an attack which comes on very, very suddenly, and causes excruciating pain in the joints, most typically the bunion joint at the base of the big toe. Typically the joint will be very, very swollen, very red, and very tender.

That attack will last for anything from a few days up to a couple of weeks and then will start to get better, even without treatment. The person then often goes back to normal, the attack goes away completely, and then over a variable period of time, which may be a few months or even a couple of years, they may not have another attack. And then all of a sudden they’ll have another attack, which again gets better. Over the course of years people will go on to have recurrent attacks, and these may become closer together and start to involve different joints. With the passage of time people may also start to develop lumps of uric acid crystals underneath the skin, typically around the elbows, in the feet, or affecting the ears.

Once uric acid crystals have started to form in and around peoples joints, uric acid crystals are usually found packed within the cartilage that’s lining the end of the bones. What happens then is that the crystals can be shaken loose into the joint space, and it’s then that they can lead to an attack of gout. So crystals of uric acid are very irritant to the joint, and they are rapidly recognised by the body’s immune system and by the cells of the immune system, and that leads to a very quick and very severe inflammatory reaction, which causes the very intense pain that’s associated with gout.