Hyperglycaemia is the medical term for a high blood sugar (glucose) level. It’s a common problem for people with diabetes.
It can affect people with type 1 diabetes and type 2 diabetes, as well as pregnant women with gestational diabetes.
Symptoms of hyperglycaemia
Symptoms of hyperglycaemia in people with diabetes tend to develop slowly over a few days or weeks. In some cases, there may be no symptoms until the blood sugar level is very high.
Symptoms of hyperglycaemia include:
- increased thirst and a dry mouth
- needing to pee frequently
- blurred vision
- unintentional weight loss
- recurrent infections, such as thrush, bladder infections (cystitis) and skin infections
- tummy pain
- feeling or being sick
- breath that smells fruity
Symptoms of hyperglycaemia can also be due to undiagnosed diabetes, so see your GP if this applies to you. You can have a test to check for the condition.
If you’ve been diagnosed with diabetes and you have symptoms of hyperglycaemia, follow the advice your care team has given you to reduce your blood sugar level.
If you’re not sure what to do, contact your GP or care team.
You may be advised to:
- change your diet – for example, you may be advised to avoid foods that cause your blood sugar levels to rise, such as cakes or sugary drinks
- drink plenty of sugar-free fluids – this can help if you’re dehydrated
- exercise more often – gentle, regular exercise such as walking can often lower your blood sugar level, particularly if it helps you lose weight
- if you use insulin, adjust your dose – your care team can give you specific advice about how to do this
You may also be advised to monitor your blood sugar level more closely, or test your blood or urine for substances called ketones (associated with diabetic ketoacidosis).
Until your blood sugar level is back under control, watch out for additional symptoms that could be a sign of a more serious condition.
When to get urgent medical attention
Contact your diabetes care team immediately if you have a high blood sugar level and experience the following symptoms:
- feeling or being sick
- abdominal (tummy) pain and diarrhoea
- rapid, deep breathing
- fever (38C or above) for more than 24 hours
- signs of dehydration, such as a headache, dry skin and a weak, rapid heartbeat
- difficulty staying awake
These symptoms could be a sign of a more serious complication of hyperglycaemia, such as diabetic ketoacidosis or a hyperosmolar hyperglycaemic state and you may need to be looked after in hospital.
How to prevent hyperglycaemia
There are simple ways to reduce your risk of severe or prolonged hyperglycaemia:
- Be careful what you eat – be particularly aware of how snacking and eating sugary foods or carbohydrates can affect your blood sugar level.
- Stick to your treatment plan – remember to take your insulin or other diabetes medications as recommended by your care team.
- Be as active as possible – getting regular exercise can help stop your blood sugar level rising, but you should check with your doctor first if you’re taking diabetes medication, as some medicines can lead to hypoglycaemia if you exercise too much
- Take extra care when you’re ill – your care team can provide you with some “sick day rules” that outline what you can do to keep your blood sugar level under control during an illness.
- Monitor your blood sugar level – your care team may suggest using a device to check your level at home, so you can spot an increase early and take steps to stop it.