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High Blood Sugars

High blood sugars or hyperglycaemia

Hyperglycaemia is the medical word for high blood sugar/glucose levels. High glucose levels can affect people in lots of different ways, and they are called the symptoms of diabetes.

 Symptoms of diabetes

  • Tiredness – this is because your body cannot convert the sugar in your blood stream into energy
  • Passing more urine– as your blood sugar levels start to rise your kidneys try to remove the extra sugar out of your blood and into your urine. This takes water with it, and so you produce larger volumes of urine, pass urine more frequently, and often people have to get up in the night to pass urine as well.
  • Thirst – As a result of passing more urine your body gets dehydrated, and so you feel thirsty to catch up. Water is the best drink to make up for this, but quite often, if the person doesn’t know they are developing diabetes, they might drink sugary drinks or fruit juices. Unfortunately, the sugar in these drinks just makes the problem worse, and it feels like the thirst just can’t be quenched.
  • Blurred vision – If your blood sugar level is high, this temporarily affects how much water is in the eye changing its shape, causing the vision to blur. By reducing your blood sugar levels your eyesight will return to normal in a short space of time.
  • Cystitis and Thrush – bugs like bacteria and fungi use sugar as fuel too. So if there is a lot of sugar in your urine, because there is a lot in your blood, these sorts of infections are more likely.
  • Weight loss – when blood sugar levels are very high, sugar escapes into the urine, this will cause people to lose weight. This is not particularly common in Type 2 diabetes.

Causes of high blood sugars (hyperglycaemia)          

  • Lack of insulin – sugar levels can rise because there is not enough insulin present
  • Insulin resistance – the insulin that is produced does not work properly
  • Eating too much – generally, sugary or starchy food and drink will cause blood glucose levels to rise. The more you eat, the higher your blood sugar levels get.
  • Taking less exercise than normal – exercise usually burns off sugar, so taking less exercise than normal, may lead to a rise in blood sugar levels.
  • Illness – If you are suffering from an illness, infection or are under a lot of stress this affects other hormones in your body, and this can cause high blood sugars(hyperglycaemia)
  • Medications – Certain medications, especially steroids, can interfere with your blood glucose regulation and cause high blood sugars.
  • Alcohol – Alcohol usually causes low blood sugars, but some drinks have a surprising amount of carbohydrates in them, and so this can be a bit unpredictable.

Treatments of high blood sugars (hyperglycaemia)

 A good thing to do is try and establish a cause for your raised blood sugar levels. If, for example, you have been eating too many sugary or starchy foods – try to reduce them and see the effect on your blood sugar levels.

If you have been less active than normal – try and increase your activity levels again if possible.

If you can see no cause for your high blood sugars (hyperglycaemia) and it’s persistent, then it would be advisable to contact your health care professional to see if your treatment needs adjusting.

Importance of optimum control

The aim of good control for your diabetes is to be free of the symptoms we have discussed and to reduce the risks of long term complications.

Therefore it is essential to know when to seek help with your high blood sugars.

What to do when you are not well

When people are unwell, diabetes control can seem to go haywire. Stress hormones put blood sugars up, but feeling sick often means you eat less so it can be very hard to predict what will happen.

Please follow these “sick day rules” to keep your diabetes safe, when you are poorly.

  • NEVER stop taking your tablets or insulin – this is because your body’s need for insulin is usually increased during illness.
  • Test your blood sugars frequently 2 – 4 hourly.
  • Aim to drink at least 2.5litres or 5 pints of water or sugar free fluid per day to prevent dehydration
  • Rest and avoid strenuous exercise to avoid further increasing your blood glucose levels.
  • Eat as normally as you can. If you cannot eat then replace solid food with one of the following 400 mls of milk, 150-200mls non diet fizzy drink, 200mls carton fruit juice, 1 scoop of ice-cream

 When to seek further help from doctor or nurse

 If someone has any of the following they must seek advice from their health care professional.

  • Continuous diarrhoea or vomiting
  • Unable to keep food down for more than 4 hours
  • High blood glucose levels with symptoms of illness
  • Becoming drowsy or confused

This will be discussed in greater detail in the section called “Illness”.