Diabetic ketoacidosis (DKA) is a serious problem that can occur in people with diabetes if their body starts to run out of insulin.

This causes harmful substances called ketones to build up in the body, which can be life-threatening if not spotted and treated quickly.

DKA mainly affects people with type 1 diabetes, but can sometimes occur in people with type 2 diabetes. If you have diabetes, it's important to be aware of the risk and know what to do if DKA occurs.

Symptoms of diabetic ketoacidosis

Signs of DKA include:

• needing to pee more than usual
• feeling very thirsty
• being sick
• tummy pain
• breath that smells fruity (like pear drop sweets or nail varnish)
• deep or fast breathing
• feeling very tired or sleepy
• confusion
• passing out

DKA can also cause high blood sugar (hyperglycaemia) and a high level of ketones in your blood or urine, which you can check for using home-testing kits.

Symptoms usually develop over 24 hours, but can come on faster.

Check your blood sugar and ketone levels

Check your blood sugar level if you have symptoms of DKA.

If your blood sugar is 11mmol/L or over and you have a blood or urine ketone testing kit, check your ketone level.

If you do a blood ketone test:

• lower than 0.6mmol/L is a normal reading
• 0.6 to 1.5mmol/L means you're at a slightly increased risk of DKA and should test again in a couple of hours
• 1.6 to 2.9mmol/L means you're at an increased risk of DKA and should contact your diabetes team or GP as soon as possible
• 3mmol/L or over means you have a very high risk of DKA and should get medical help immediately

If you do a urine ketone test, a result of more than 2+ means there's a high chance you have DKA.

When to get medical help

Go to your nearest accident and emergency (A&E) department straight away if you think you have DKA, especially if you have a high level of ketones in your blood or urine.

DKA is an emergency and needs to be treated in hospital immediately.

Call your diabetes team or GP as soon as possible if you're not sure if you need emergency help – for example:

• your blood sugar or ketone levels are high or getting higher over time but you don't feel unwell
• you feel unwell but your blood sugar or ketone levels are normal or are only a little bit higher than usual

If you can't contact your care team or GP, call your local out-of-hours service or NHS 111 for advice.

Causes of diabetic ketoacidosis

DKA is caused by a lack of insulin in the body, which causes the body to break down fat for energy. Ketones are released into the body as the fat is broken down.

If you have diabetes, certain things can make this more likely to happen, including:

• having an infection, such as flu or a urinary tract infection (UTI)
• not following your treatment plan, such as missing doses of insulin
• an injury or surgery
• taking certain medicines, such as steroid medication
• binge drinking
• using illegal drugs
• pregnancy
• having your period

In some cases there's no obvious trigger.

Preventing diabetic ketoacidosis

The following tips can help reduce your chances of getting DKA:

• check your blood sugar regularly so you can spot and treat an increase quickly – read about how to treat high blood sugar
• stick to your treatment plan – don't stop taking insulin unless told to by a healthcare professional
• take extra care when you're ill – your diabetes team can give you some "sick day rules" to follow, which include things like checking your blood sugar more often and checking your ketone level
• be careful taking new medicines – check with a doctor or pharmacist first, as some medicines can increase the risk of DKA

Contact your diabetes team or GP for advice if you find it hard to keep your blood sugar level down.

Treatments for diabetic ketoacidosis

DKA is usually treated in hospital.

Treatments include:

• insulin, usually given into a vein
• fluids given into a vein to rehydrate your body 
• nutrients given into a vein to replace any you've lost

You'll also be closely monitored for any life-threatening problems that can occur, such as problems with the brain, kidneys or lungs.

You can leave hospital when you're well enough to eat and drink and tests show a safe level of ketones in your body. It's normal to stay in hospital for a couple of days.

Before leaving hospital, ask to speak to a diabetes nurse about why DKA occurred and what you can do to stop it happening again.