Question from Austin, Texas, USA:

My son is beginning to give his own shots and last week, he apparently drew up 6 units of air. My husband checked for air bubbles, and there were none. My son gave himself the injection with all seeming to be routine, but four hours later, his blood sugar was nearly 500 mg/dl [27.8 mmol/L] (which is highly unusual). We could not think of any reason it should jump so high — usually we can figure out what didn’t go quite right. The sugar level came down with a correction dose..

Later, while watching my son draw up the insulin, I realized he probably did not get any insulin in the syringe that day as his technique was to hold the bottle and syringe in a horizontal position while drawing up the insulin. He now holds it vertically. My husband now knows how to determine if there is insulin in the syringe. I would think that injecting air would at least would be painful — but the only symptom was the high blood sugar. What are the consequences of injecting air just under the skin?