Don’t forget the insulin on board. Even rapid-acting insulin can take four hours or more to finish working. If you still have active insulin in your system at bedtime from injections or boluses given earlier in the day, deduct it from any correction doses that you would ordinarily give yourself. If you have a great deal of insulin on board and have not eaten in several hours, you may need a snack to prevent a drop — depending, of course, on your current blood glucose level.
Don’t “graze” at night. Having numerous small snacks at night is asking for trouble. Instead, limit your snacks to just one at night, count the amount of carbohydrate accurately, and use an insulin-to-carbohydrate formula that produces normal blood glucose levels 3–4 hours later. Grazing (with frequent shots or boluses to cover the food) causes “stacking” of insulin and may produce a significant drop after you go to bed.
Adjust for prior physical activity. Prolonged, vigorous exercise earlier in the day can make your body very sensitive to insulin for up to 24 hours. It also causes your muscles to absorb extra glucose to replace their glycogen stores. The same can happen when you travel (if you do a lot of extra walking) or when the weather warms up considerably. Consider having an extra snack (without insulin) at bedtime or lowering your dose of basal insulin if you have been much more active than usual.
Think when you drink. Because alcohol can suppress the liver’s normal secretion of glucose, consider having an extra snack (without insulin) at bedtime or lowering your dose of basal insulin after drinking.
Don’t forget to check your blood glucose level. Knowing your blood glucose level at bedtime every night puts you in a position to prevent a potential low. If your blood glucose is approaching the hypoglycemic range, a modest snack (without insulin) can restore it to a normal, safer level.
Consider a CGM. Continuous glucose monitors (CGMs) have the ability to alert users when their blood glucose level is approaching the hypoglycemic range. Regular use of a CGM is associated with reduced frequency, severity, and duration of hypoglycemia in adults as well as children. A CGM can show you what direction your blood glucose level is headed at bedtime and additionally show the blood glucose patterns that occur while you sleep. Although CGMs may not detect every low, they will provide an early warning for the vast majority of lows — and much earlier than most people can detect them on their own.
Having low blood glucose during the night is not like having it during the day. It’s dark. You are likely to be groggy. And your coordination and equilibrium may be off. So think ahead: Make treating a nighttime low as easy as humanly possible.
Stick with dextrose. For treating low blood glucose, nothing works faster than dextrose — a form of glucose that is the main ingredient in most products marketed to people with diabetes for the treatment of hypoglycemia.
Use a liquid or gel. It may be difficult to chew when you’re half asleep and hypoglycemic. So instead of relying on glucose tablets, consider keeping a liquid treatment at your bedside, such as a glucose gel or bottle of liquid dextrose. Whatever you use, remove the wrappers and loosen the cap ahead of time so that it is very easy to access the container’s contents when you need it.
Have glucagon available. Injected glucagon raises blood glucose by making the liver release stored glucose. Make sure that someone who lives with you is trained on how to administer glucagon in case you are unable to eat or drink. Let that person know where you keep your glucagon kit, and replenish the kit before the contents expire.
Know the signs
The nighttime hypoglycemia specter may show up from time to time, but that doesn’t mean you can’t handle him with relative ease.