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Diabetes and other illnesses

Periods of illness such as colds or flu can have an effect to destabilise blood glucose values. Illness usually has an effect to increase blood glucose values although everyone responds differently. Generally the more severe the illness the more the blood glucose value will increase.

It is very important that people taking medicines to control blood glucose do not stop these. The doses of medicines, particularly insulin, may need to be increased during an illness.

When you are ill

The golden rules in dealing with an illness are as follows:

  • Do not stop medicines, particularly insulin treatment, during an illness.
  • Test blood glucose levels frequently (perhaps every 4-6 hours) particularly if these are high or unstable.
  • Try to keep well hydrated by drinking low calorie (sugar free) fluids. Generally you should aim for about 5 pints per day of water or other low calorie drinks.
  • If you are unable to eat or are vomiting and you are in need of calories to prevent the blood sugar falling too low try easily digestible foods such as soup, fruit yoghurt or milk. If you cannot tolerate these try sipping sugar-containing fluids such as lucozade or sucking glucose tablets or sweets.
  • People on insulin should try increasing their doses if the blood glucose values are persistently high.
  • Some people may be asked to test for ketones in the blood or urine. This can be a useful way of determining the severity of illness and that blood glucose values have become persistently high and out of control.
  • People who have persistent vomiting and are unable to tolerate any food or drink or who cannot control their blood glucose values or are just unsure what to do should seek medical help.

More detailed advice about how to deal with illness which is appropriate to your individual situation should be sought from your local diabetes team.

People who have type 1 diabetes in the UK should now be able to attend a structured education course called DAFNE which gives more specific advice about how to deal with illness and how to make adjustments to insulin doses.



Hypoglycaemia (hypos)

Hypoglycaemia (hypos)
Hypoglycaemia means having too little glucose (sugar) in the blood. Having a hypoglycaemic attack (or 'hypo') is one of the most common complications of diabetes.

Carbohydrates and diabetes

Carbohydrates and diabetes
Considering the glycaemic effect of different forms of carbohydrate can be an effective way of regulating blood glucose.


DAFNE (Dose Adjustment for Normal Eating) is a patient education programme which teaches people with type 1 diabetes the skills they need to adjust their insulin doses to match what they eat.