top of page

Drug Facts: Insulin (The Basics)

Updated: Mar 30, 2022

diabetes medications insulin with pills in the background

Insulin is a hormone our bodies produce to keep our blood sugars from going too high. Insulin is made and secreted by beta cells in our pancreas. People with type 1 diabetes do not produce any insulin at all, so they need to inject themselves with insulin regularly to survive. Many people with type 2 diabetes also use insulin, and they can use it with or without oral or other injectable medications.

There are many different types of insulin as well as different ways to administer them. Insulin is not available in pill form, as your gasrointestinal tract would just digest it like food. Insulin is generally given as a shot, but there is also a brand of inhalable insulin available on the market.

Different types of insulin have different onsets, peaks and durations. Basically, some of them work faster, while others works slower.

  • Onset – Length of time before the insulin starts to work

  • Peak – Time in which the insulin is at its maximum strength

  • Duration – Length of time before the insulin wears off


For people with type 1 diabetes, they will generally take what’s called a basal insulin, which has a long duration, so it lasts all day. This is background insulin which keeps blood sugars steady. They will also then take what’s called a bolus insulin, which is to be taken when carbohydrates are consumed to keep blood sugars from spiking. These bolus insulins have shorter onsets, peaks and durations and their job is to lower blood sugar spikes and then go away.

A lot of people with type 2 diabetes are nervous about starting insulin. Giving yourself insulin the first few times can be scary, but it’s generally painless! The needle is pretty short and skinny and it’s injected into your fat, not muscle, so most of the time you won’t even feel it. Testing your blood sugars with a finger prick hurts a whole lot more! People with type 2 or gestational diabetes may take one or two different types of insulin.

Most people inject themselves with insulin using a pre-filled insulin pen. The pen is dialed up to the correct dose and then administered using a disposable needle. A second option is using vial and syringe, which I consider to be the old school method. Using this technique, you use a syringe to pull up insulin from a bottle (also known as a vial), just like when you get a shot at the doctor’s office. This option is sometimes less expensive depending on your insurance coverage, but it’s not as convenient. I sometimes get nervous when my patients are using vial and syringe because the numbers on the syringe can be hard to read and I’m not sure if they’re giving themselves the exact amount of insulin they wanted. Thirdly, insulin can be administered using an insulin pump. Insulin pumps are computerized devices that administer insulin into the body through a catheter placed under the skin. Basically, a little needle in stuck in the skin and then a medical-grade sticker holds it into place. This is connected to tubing which is connected to the pump. Insulin pumps generally give people the best blood sugar control, and they can provide more flexibility and customization.

If you’re the type of person that has a lot of reactions to medications, insulin might be a good fit for you. Allergic reactions are rare since insulin is a hormone the body naturally produces. Some real potential side effects, however, are hypoglycemia and weight gain. If you take too much insulin, change your dietary habits, or increase activity, blood sugars can go TOO low. So if you take insulin, make sure to talk to your provider or Certified Diabetes Care and Education Specialist about the signs and symptoms of hypoglycemia as well as how to treat it. Surprised that insulin causes weight gain? A lot of people I talk to are. Insulin’s job is to move sugar out of the bloodstream and into the cells. If this sugar isn’t used as energy, it’s going to be stored as fat. Losing weight while taking insulin is very possible (I’ve personally seen it MANY MANY times), but it can be challenging at times. If you’re struggling, talk to a Registered Dietitian Nutritionist and/or Certified Diabetes Care and Education Specialist!



bottom of page