What is the reason for a sudden rise in blood sugar levels?

My friend has type 1 diabetes and is insulin dependant. He takes 2-3 shots of insulin injections everyday. Usually his blood sugar level is under control, but all of sudden his blood sugar levels have risen above 300 mg/dl. It has been more than 2 weeks now and he is not doing well. He had to be hospitalised 2 days back. The doctor could not determine any reason for a sudden rise in sugar levels. What are the probable causes for this? Please refer names of doctors or hospitals where he could get himself checked properly.


Any stress, physical (infection, trauma, heart attack etc.) or mental stress can lead to a rise in blood glucose. less insulin or expiry-date insulin or insulin exposed to higher temperature can inactivate insulin - use of such can also lead to such a rise in blood glucose. You may consult any endocrinologist for further advise.