What causes high blood glucose?

High blood glucose can result when food, activity and insulin or other medication are not balanced. High blood glucose may happen when you are ill, pregnant or under stress.

The signs of high blood glucose include –

  • Thirsty and\or dry mouth
  • Glucose in the urine
  • Large urine volumes
  • Weakness and lethargy
  • Urinating more often
  • Blurred vision
  • Weight loss


If you think you have high blood glucose, check your blood glucose levels. If you have type 2 diabetes, call or see your doctor. If you have type 1 diabetes, test your urine for ketones and seek medical advice immediately if ketones are present.

A temporary high blood glucose level does not require any emergency measures at all. Always check for ketones in the urine. The absence of urine ketones means that the cells are not starved. If you feel well, measure the blood glucose level again before your next meal and if necessary, add another 1-2 units of short acting insulin to your pre-meal dose if levels are still high.