Colchicine: gout attacks, spacing doses and grapefruit

The NHS describes colchicine as a medicine mainly used for gout that reduces pain and joint inflammation. It is used for a short time to relieve symptoms of a gout attack, and to prevent attacks that may happen when you first start taking other medicines for gout, which lower uric acid. It is also used to prevent symptoms of familial Mediterranean fever, a rare genetic condition.

It does not lower uric acid itself. That is the job of medicines such as allopurinol and febuxostat, which is why colchicine often appears alongside them in the first weeks.

Colchicine comes as tablets, swallowed whole with a glass of water. The amount and length of treatment depend on why you are taking it, and your doctor will explain your dose. The NHS stresses one point above all: do not take doses closer together than your doctor has told you, because too much can build up in your body and cause serious side effects.

If you miss a dose, take it when you remember unless the next dose is close, in which case skip the missed one. Never take two together. If you are unsure what to do, ask a pharmacist or doctor. Extra doses can be dangerous, so seek help if you have taken more than prescribed, and if sent to A&E, do not drive.

The NHS lists serious effects rather than a common-effects list. The first sign of too much medicine (toxicity) is stomach pain, nausea, vomiting and diarrhoea, so these symptoms deserve attention rather than being put up with.

Other serious effects include bone marrow problems (high temperature, bruises, or prolonged bleeding after an injury), nerve problems (pain, tingling, loss of feeling and weakness), muscle and kidney problems (muscle pain or weakness and dark red or brown urine) and anaphylaxis. Call 999 for anaphylaxis and 111 for any other serious effect. It will not usually affect driving, but wait if you feel sleepy or dizzy.

Most adults can take it, and it is sometimes prescribed for children. It may not suit someone who has had an allergic reaction or serious side effect from it, or who has a blood condition, kidney problems or is on dialysis, a digestive condition such as a stomach ulcer, Crohn disease, ulcerative colitis or coeliac disease, or liver or heart problems.

It can be used in pregnancy if needed, after your doctor weighs risks and benefits, so tell them if you are pregnant or become pregnant. You may be able to take it while breastfeeding, but check with a doctor or pharmacist first.

The NHS lists statins, some antibiotics such as erythromycin and clarithromycin, some heart medicines such as verapamil, diltiazem and digoxin, HIV medicines such as ritonavir, cimetidine and ciclosporin as medicines that may not mix well. Statin combinations are the one most often raised in clinics because of muscle effects, so tell the prescriber about every cholesterol medicine you take.

You can eat as normal, but do not drink grapefruit juice because it can increase the amount of colchicine in your blood, which can be dangerous.

An attack is only part of the picture. Long-term control rests on lowering uric acid, with blood tests to track it, and on factors such as diet, alcohol, body weight and other medicines. Colchicine is one of several options for attacks; NSAIDs such as naproxen and steroids are others, chosen according to other health conditions, which is a conversation for your doctor.