I Accidentally Took 18 Units of the Wrong Insulin


For some people living with type 2 diabetes (T2D), using insulin is a necessity to keep blood glucose levels in range. But taking too much insulin can lead to hypoglycemia (low blood sugar). While high blood sugar gets a lot of attention in discussions about T2D management, low blood sugar should be taken just as seriously. Severe low blood sugar requires emergency assistance by others, as well as the use of an emergency treatment called glucagon. Severe low blood sugar can cause seizures, fainting and falling into a coma.

If you’re taking insulin—mealtime or long-acting—this is just another reason why it’s important to know how much you’re taking and make sure you’re taking the right kind of insulin. Just ask Jean, who accidentally took 18 units of mealtime insulin when she thought she was taking her long-acting.

“I’ve been on long-acting insulin for about eight years and mealtime insulin for about five,” said Jean who has been living with type 2 diabetes for 19 years after experiencing gestational diabetes. “I have, indeed, forgotten to take the long-acting at night. Sometimes it gets to be so routine, you go to bed and ask yourself if you’ve taken it or not. I usually take 18 units of my long-acting at night and take my mealtime once a day or when I need it for a large meal. One night, I went to bed and took 18 units of mealtime insulin. As soon as I injected it, I knew I’d messed up and had to watch out for low blood sugar.”

Though Jean was fine, she ended up making the same mistake a second time.

“The second time I did it, I thought I had my bases covered,” says Jean. “But you make mistakes, and it just happens. That time, I set my alarm and my blood sugar wasn’t high when I went to bed, which meant I’d really set myself up for disaster. I had to set my alarm on my phone about every 45 minutes to an hour to check my blood sugar throughout the night. I ended up eating food over that night and got through it. But, it was really frightening. It can happen to the best of us, and if it does, you have to be alert.”

Typically, Jean checks her blood sugar about four times per day. Though they’re commonly used to treat low blood sugar, she tries to not buy juice or sweets. However, her husband does, which means she must carefully decide how much she eats or drinks if her blood glucose levels drop low. Jean, who works as a nurse and cares for elderly patients in a cataract surgery center, is aware of glucagon as an emergency treatment option but opts for juice or chocolate milk to take care of her low blood sugar.

Creating your own way to keep track of how much insulin you take each day is important to prevent skipping dosages or accidentally taking too much. While she’s not a fan of using apps or journals, Jean uses a paper grid to cross out if she needed to use rapid-acting insulin at mealtime and how much. Regarding her long-acting? Since she has a set number that she takes each night, making it easy to remember how much she’s using each day.

Jean’s comfort with using insulin to manage type 2 diabetes wasn’t always evident. When recalling the first time it was suggested she start insulin, Jean admits she felt like a failure, even though her endocrinologist assured her of its benefits. Jean felt she didn’t do enough watching or diet and felt like she didn’t exercise enough to stave off the need to use insulin to manage her diabetes.

“I had people assume my diabetes must’ve been really bad,” said Jean. “But I started to think of it this way: your body is like a car and the parts wear out. I’m just doing maintenance on it. I’m taking medicine and I’m not embarrassed about it anymore. Initially, I think a lot of people felt the way I did; that I messed up or failed somehow. But I don’t think that’s right. I don’t think that’s the right way to feel.”

Part of that acceptance is understanding diabetes differs for everyone. “You can take two people with type 2 diabetes, same body size, height and weight and even lifestyle. You can give them the same food and their blood sugar will differ. I could eat the same thing I’m eating today and have it tomorrow, and my blood glucose can be different on both days. There’s no rhyme or reason to diabetes, sometimes. What matters is to know it’s never your fault that you have diabetes or need insulin to manage it.”

This content was made possible with support from Lilly Diabetes. Beyond Type 2 maintains full editorial control of all content published on our platforms.

Written By T'ara Smith, MS, Nutrition Education, Posted , Updated 09/03/23

T’ara was diagnosed with type 2 diabetes in July 2017 at the age of 25. Since her diagnosis, she focused her academic studies and career on diabetes awareness and living a full life with it. She’s excited to have joined the Beyond Type 1 team to continue her work. Two years later, T'ara discovered she'd been misdiagnosed with type 2 and actually has latent autoimmune diabetes in adults (LADA). Outside the office, T’ara enjoys going to the movies, visiting parks with her dog, listening to BTS and cooking awesome healthy meals. T’ara holds an MS in Nutrition Education from American University.