Diabetes type 1

Highs (hyperglycaemia)

Hyperglycaemia, or high as it is often called, means a higher than normal level of glucose in the blood. If your blood glucose gets very high (above 17mmol/l), you should always check for ketones in your blood or urine. If tests show ketones in two or more tests in a day or if you feel unwell (e.g. if you are vomiting) follow your sick day rules or seek medical advice if you are unsure. Continuing high blood sugar, especially if combined with ketones in the urine, must be taken seriously.

Symptoms of hyperglycaemia

Symptoms of highs are the same as those of untreated diabetes: thirst, frequent urination (peeing) and tiredness. The most common reasons for highs are a mismatch of insulin to the amount of carbohydrate eaten/drunk, but infection or illness can also send blood sugar high, and some people find they can go high when they are stressed, frightened or excited.

Having constantly high blood glucose levels increases the risks of developing complications of diabetes. When there are complications, the parts of the body most likely to be affected are: eyes, kidneys, peripheral nerves in the hands, legs and feet, the skin and large blood vessels. The check-ups you are offered at clinic are designed to pick up any signs of these complications as early as possible so any problems can be sorted out quickly.
Maintaining a stable blood glucose level is sometimes very difficult for people on insulin.

Many young people said that they found it easier to recognise hypo symptoms than highs, particularly when their blood glucose is only moderately high. If you do regular blood glucose tests rather than just relying on how you feel, you can keep an eye on exactly how your blood sugar is reacting and keep yourself within safe limits.

Learning to control highs

Some young people indicated that they have had very few highs or hypos since diagnosis and attributed this to checking their blood glucose levels several times during the day particularly around meal times. Those on insulin pump therapy said that they have found it easier to control highs or hypos since they started using one. One young woman said that she could then use her blood glucose result as a guide as to how much carbohydrate she needed to eat at that particular meal. One young man who was diagnosed at the age of 16 initially had a period of high blood glucose levels but  he followed the advice from his consultant and eventually his levels became more stable.

Young people said that one common reason why they go high sometimes is that they have not injected enough insulin to cover what they have eaten. Some young people said that they might not inject if they are just having a snack or if they wake up late. Missing injections at school could also contribute (see also 'Insulin: Doing injections everyday' and 'Diet and diabetes'). Some young people experienced their glucose levels going high after drinking sugary drinks, or alcopops.
The young people we talked to said that, if they have a series of high results, they will try and find the reasons for it. The reasonsthey found included: eating different foods or more than usual, having sugar without realising it, carbohydrate/insulin ratio being insufficient, working overtime or revising for exams and not doing as much physical activity as usual. In general, a change a routine tended to be the underlying cause of highs.
Young people said that running high blood glucose levels could make them feel miserable, angry and depressed. Many talked of feeling lethargic and unable to concentrate during school lessons. Young people suggested that controlling blood glucose levels was the most difficult during the teenage years.
A number of young people said that they preferred their blood glucose level to be a bit higher rather than lower because they didn't want to risk having a hypo in front of friends or at school or when they're alone, particularly if they've had experiences of going very low and losing consciousness.
Checking for ketones

Some young people said that it is a good idea to check for ketones if you have high blood glucose levels. Ketones are an acid that builds up in the blood stream when the body burns its own fat for energy. Leaving it untreated can lead to diabetic ketoacidotic coma. One young woman said she uses Ketostix to check her urine for ketones whenever she thinks she has high blood glucose levels. Another young woman, who has had several episodes of diabetic ketoacidosis (DKA), has been told by her nurse what to do if she finds ketones in her urine.

Some young people we talked to used not to inject insulin on a regular basis and ran high blood glucose levels for long periods of time as a result. They found that bringing their blood glucose levels down again can be very difficult both physically and emotionally because when you have been running high for a while, you can still get hypo warning symptoms when your blood sugar levels start to drop - even though the blood test meter says you are not low enough to be 'officially' hypo.
High blood glucose levels and complications

Several of the young people we talked to have developed diabetes-related complications as a direct result of having high blood glucose levels for years. One young woman developed complications that lead to her been registered blind at the age of 23. Another young woman has developed a skin complication called scleroderma diabeticorum and doctors have also found that the tiny blood vessels in her eyes are leaking. 

One young woman indicated that doctors tend to talk much more about hypos and its complications but feels that highs can also be potentially dangerous and not enough emphasis and advice is given to teenagers on this subject.
Most young people said that it is very important to tell others around you that you have Type 1 diabetes. They said that you should always teach your friends about the signs of a hypo and a high and what to do in those situations. (See also 'Support from parents and families' and 'Friends and relationships'). They also said that if you are going out, it's a good idea to wear a diabetes pendant or some diabetes-type of identity so the paramedic will know exactly what to do with you if you end up unconscious.

Last reviewed December 2017.
Last update December 2017.


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