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Using Insulin Properly

Insulin is an important part of your care plan. Here are tips.

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If you have diabetes, you know how important it is to manage your insulin well. Not enough can let your blood sugar stay too high.  Too much insulin can cause potentially life-threatening low blood sugar. Be sure to know the symptoms of low blood sugar and what to do if you find yourself in that situation. Remember, some people don’t sense when they have low blood sugar. Work with your doctor if this may be the case for you.

You use insulin because your body doesn't make enough or use what you make properly. It's especially important to check your blood sugar as directed by your doctor when you are on insulin therapy.

The most common way to get insulin into the body is by using a syringe, but insulin pens and pumps are also available, as well as inhaled insulin.

If you use insulin, here are some tips:

  • Be careful when drawing up two different types of insulin. You may take two different types of insulin each day. Follow your doctor's instructions carefully when you mix insulin. Ask your doctor about the possibility of using an insulin pen for rapid-acting doses.
  • Store insulin properly. Heat, extreme cold or direct sunlight can harm the effects of insulin. If you have insulin delivered to your door, make sure it's not left in the hot sun or in very cold temperatures.
  • Replace your insulin when it is expired. Rapid-acting insulin should be replaced after one month if kept at room temperature. Intermediate-acting insulin should be kept cool or refrigerated (below 86 degrees F) but not frozen. Opened vials must be used within 28 days, whether or not they are stored in the refrigerator.
  • Talk to your doctor if you are sick. The stress caused by being sick may affect blood sugar levels. Because of this, your insulin dosage may need to be adjusted. Develop a sick day plan with your doctor including how much insulin to take and when to call your doctor.
  • Time your travel. If you’re a globetrotter who’ll be crossing several time zones on a trip, be sure to check with your doctor before you leave. You may need to change the times you take your insulin.
  • Take precautions when you travel by air. If you can, bring your prescription labels for your medicines and medical devices. Pack your medicines separately in a clear bag that you can seal. You’re allowed to carry on your diabetes supplies, so bring extra insulin and dispensing products Bring along snacks or something with sugar to help in case of low blood sugar. If you use syringes, bring a note from your doctor.
  • Make an emergency kit. Unexpected events happen. Aim to store at least seven days’ worth of diabetes supplies, including your insulin and insulin delivery supplies. Consider keeping a two-week supply of your prescription medicines and diabetes supplies. Keep them in an easily identifiable container in a place that you can readily get to.

Know what to do in an emergency. In a natural disaster, you may have access to insulin that you do not normally take. The U.S. makers of insulin recommend refrigerating insulin (36 degrees F to 46 degrees F). You may or may not have access to refrigeration. Strive to keep the insulin as cool as you can. If you use ice, avoid freezing the insulin. Do not use insulin that has been frozen.

By Susan G. Warner, Contributing Writer

American Diabetes Association. Standards of medical care in diabetes — 2015. Diabetes Care. 2015;S1-S99. Accessed: October 8, 2015.
National Diabetes Information Clearinghouse. What I need to know about diabetes medicines. Accessed: October 8, 2015.
Centers for Disease Control and Prevention. Prepare for diabetes care in heat and emergencies. Accessed: October 8, 2015.

Last Updated: October 20, 2015