INSULIN - Watsons Health




Insulin is a hormone made in your pancreas, a gland located behind your stomach. Its two main functions are:

  • Allows your body to use glucose for energy- Glucose is a type of sugar found in many carbohydrates. The digestive tract breaks down carbohydrates and changes them into glucose. Glucose is then absorbed into your bloodstream through the lining in your small intestine. Once glucose is in your bloodstream, insulin causes cells throughout your body to absorb the sugar and use it for energy.
  • Helps balance your blood glucose levels– When there’s too much glucose in your bloodstream, insulin signals your body to store the excess in your liver. The stored glucose isn’t released until your blood glucose levels decrease, such as between meals or when your body is stressed or needs an extra boost of energy.

Insulin as treatment for diabetes

Injections of insulin as a replacement or supplement to your body’s insulin can help treat both types of diabetes. People with type 1 diabetes can’t make insulin so they must use insulin to control their blood glucose levels. Insulin is also needed by people with type 2 diabetes to control their blood glucose levels in case that other treatments failed, like change in lifestyle or oral medications.



The makeup of different types of insulin affects how fast and how long they work to help mimic the natural increases and decreases of insulin levels throughout the body during the day.

  • Rapid-acting insulin: This type of insulin is often used before a meal. It begins working approximately 15 minutes after injection. Its effects can last between two and four hours.
  • Short-acting insulin:  It starts working 30 to 60 minutes after you inject it and lasts five to eight hours. You inject this insulin before a meal.
  • Intermediate-acting insulin: This type of insulin starts working in 30 minutes to an hour after injection. Its effects may last up to eight hours.
  • Long-acting insulin: This insulin may not start working until about two hours after you inject it. However, it can last up to 24 hours.

Insulin reaction may happen when you take insulin. It may cause hypoglycemia or too low blood glucose levels. This happens if you exercise too much or don’t eat enough. In that case, you need to balance the insulin that you give yourself with food or calories. Symptoms of insulin reactions include:

  • tiredness
  • inability to speak
  • sweating
  • confusion
  • loss of consciousness
  • seizures
  • muscle twitching
  • pale skin



To stop the effects of an insulin reaction, carry at least 15 grams of a fast-acting carbohydrate with you at all times. That’s about equal to any of the following:

  • 1/2 cup of non-diet soda
  • 1/2 cup of fruit juice
  • 5 lifesaver candies
  • 2 tablespoons of raisins

Ask your doctor about a special pen called glucagon pen to help resolve an insulin reaction.



You must inject insulin with a syringe, insulin pen, or insulin pump because you can’t take it by mouth. The type of insulin injection you use will be based on your personal preference, health needs, and insurance coverage.

You can inject the insulin under the skin in many different parts of your body, such as your thigh, buttocks, upper arm, and abdomen. Don’t inject insulin within two inches of your belly button, though — your body won’t absorb it as well. You should vary the location of injections to prevent the thickening of your skin from constant insulin exposure.

Insulin helps keep your blood glucose level within a healthy range so used it appropriately. Healthy blood glucose levels help reduce the risk of diabetes complications, such as blindness and the loss of limbs. If you have diabetes, it’s important that you monitor your blood glucose level regularly. You should also make lifestyle changes to prevent your blood glucose level from getting too high. And of course, talk to your doctor about how you can make your treatment with insulin as effective as possible.

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