has any one had simular when having a cold I've eaten nothing since 6pm last night and drunk 500ml of diet tonic water and 250ml of coke zero I take 1 sitagliptin per day at 8 am
Your liver preserving you with a glucose dump whilst you're in fasting mode. Its very very normal. In more severe diabetics it rises to 30s without insulin.
Keep hydrated if you can. If sickness persists for more than the normal sickness bug 24hrs call 111 if in UK.