People often ask what it means when their meter flashes “test ketones”. This article will outline everything you need to know about ketones and ketone testing.
What are ketones?
Ketones are produced in the blood from the breakdown of fat. Your body produces ketones when you don’t have enough insulin in your body to turn sugar (or glucose) into energy. You need another source of energy, so your body uses fat as fuel instead. When you have diabetes, you can build up too many ketones in your blood – and too many ketones can become life-threatening.
What causes high ketones?
Situation # 1: The body needs more insulin.
In people with type 1 diabetes, ketones are made because there is a relative lack of insulin. In this situation, their blood sugars are also usually high. So some meters will give a prompt to test ketones if the blood sugar reading is over 15 mmol/L.
Reasons for high ketones may include:
- Forgetting to take insulin
- Using insulin that is no longer active (for example: if the insulin gets too hot or cold)
- An insulin pump that is disconnected or not working properly
- Dehydration (for example: vomiting with the flu)
Situation # 2: Not eating enough.
Ketones can also form when someone has not eaten enough food and is in a “starving state”. In this case blood sugars are normal or low and this can happen to people without diabetes but can also happen to people with diabetes if they are not consuming enough calories. Pregnant women with gestational diabetes are more prone to high ketones due to not eating enough.
What are the symptoms of elevated ketones?
It is important to be aware of the symptoms that can occur when you have high ketones. These include:
- Dry mouth
- Blood sugars greater than 15 mmol/L*
- Increased thirst
- Frequent urination
*may be less than 15 mmol/L if on an SGLT2 inhibitor
Symptoms that require more urgent assessment and/or treatment in hospital setting include:
- Breath has a “fruity” smell
- Stomach pain
- Extreme fatigue
- Increased breathing rate (more rapid breathing)
- Trouble breathing
It is important to always seek medical attention if your ketones are high!
When is high, too high?
A build-up of ketones changes the delicate pH balance in the blood, making your blood acidic. This can cause a condition called diabetic ketoacidosis (DKA), which can be a life-threatening situation.
DKA can result in:
- Loss of consciousness
- Diabetic coma
- Swelling of the brain
- This is why prompt treatment of high ketones is so important!
When should I test for ketones?
You should test your urine or blood for ketones in any of the following situations:
- Your blood sugar is higher than 15 mmol/L
- You have symptoms of diabetic ketoacidosis (DKA) such as frequent urination, extreme thirst, nausea/vomiting, confusion, and fruit-smelling breath
- You are sick and are not eating or drinking well and/or nauseated and vomiting
How do I test for ketones?
One can test for ketones in the urine or the blood. Urine ketone strips can be bought without a prescription and turn a dark colour after 15 seconds once dipped into urine. The amount of ketones is indicated by how dark the strip turns. This is usually the way a woman with gestational diabetes tests her urine.
Another method which is more accurate in distinguishing the type of ketones, that is, either lack of insulin or starvation, is to test the blood. There are some meters that have strips, very similar to blood glucose testing strips, that will indicate the level of ketones. People with type 1 diabetes and particularly children and their families, are often taught this type of ketone testing.
What is the treatment for high ketones?
Early treatment can help you avoid hospitalization or developing DKA. Speak to your healthcare team to come up with a plan to manage high ketones. If you cannot manage high ketones on your own, it is important to seek medical treatment which can include:
- Intravenous (IV) fluid replacement: it is important to rehydrate with fluids to help dilute extra sugar in your blood.
- Electrolyte replacement: when a person has high ketones or DKA, their electrolyte levels (such as potassium, and sodium) tend to be low. It is important to replenish electrolytes that are low to keep the heart and muscles functioning well.
- Intravenous (IV) insulin: people are usually given insulin to reduce excess sugar in their blood.
How do I prevent high ketones?
Prevention is really important. Proper management of your diabetes is the best way to prevent high ketones. This includes:
- taking all medications and insulin as prescribed
- checking your blood sugars regularly
- following a healthy diet
- having a sick day plan
- knowing what to do when your ketones get too high