INSULIN & TRAVEL
Thomas Higgins, M.D.
There are several general recommendations for travel with insulin:
Keep your insulin & syringes with you in carry-on luggage
Separate your insulin into two separate bags in the event an insulin bottle should break or a bag is stolen or lost.
Do not allow insulin to freeze or cook. Insulin does not need to be continuously refrigerated.
Keep your home glucose monitoring equipment & insulin reaction supplies with you.
Travel North or South is generally not a problem but travel East or West may require some adjustment in you insulin dosage if the travel involves a significant time change. Travel eastward effectively shortens the day while travel westward lengthens the day of travel. I generally recommend a change in the long acting insulin with the direction of change based on the direction of travel and the amount of changed based on the fractional change in the time of day.
As an example: you are taking 20 units of NPH & 5 of regular in the am & 10 units of NPH & 5 regular before supper as a stable insulin dose. Your insulin dose and blood sugar control are stable You plan a trip to London with an intermediate stop in New York. The trip begins in the afternoon & continues overnight to London. The Denver to New York leg involves a 2-hour time change and there is an additional 5-hour change from New York to London. The fractional change in the day is 2/24 for the leg from Denver to New York and 5/24 from New York to London. Since you are traveling eastward, the trip will cause a decrease in the effective length of the day of travel. You may want to decrease your morning long acting insulin by 2/24. The overnight long acting insulin should be decreased by 5/24 and taken on New York Time. Doing the math results in a 1.7 unit decrease in the morning NPH & a 2.1 unit decrease in the overnight NPH. Rounding off to 2-unit reduction in each dose seems like an appropriate estimate. When you arrive in London, you take your morning injection on London time. Returning from London involves similar but in a positive direction & with respect to time & insulin dose. Again, the long acting insulin to change is the one that is active during the flight.
Changes in rapid acting insulin (regular & Humalog) should be based more on the meal size that you anticipate during the trip than on time changes some decrease may be appropriate for airline food.
Persons traveling with insulin pumps can simply change the pumps internal clock to the local time after each leg of the trip and continue their usual meal bolus schedule.
It is important to monitor you blood sugar closely and be prepared to treat both insulin reactions and high blood sugar promptly. Testing the blood sugar prior to the flight & half way through long flights is prudent. Supplemental insulin for glucose values over 240 mg% should be rapid acting insulin and the amount based on your own experience with your insulin sensitivity. Raisins or hard candy are good supplies for insulin reactions. If you are subject to severe insulin reactions where you are unable to help yourself, carry a glucagon kit and be sure your travel partner knows how to use it. If you are traveling alone, insure that the stewards know you have diabetes and where you are keeping your glucagon kit & glucose monitor.
It must be remembered that the above recommendations are only an initial approximation and you may want to discuss your travel plans with your doctor or diabetes nurse educator.