What Is Lipohypertrophy?

Table of Contents
View All
Table of Contents

Lipohypertrophy is a fairly common condition for people with diabetes. A lump of fat and sometimes scar tissue is formed under the skin from repeated insulin injections or infusions. It occurs most often in people with diabetes who must undergo multiple daily injections, but can also occur in people who wear multiple devices such as an insulin pump and continuous glucose monitor.

Notwithstanding advancements in diabetes technology and medications, this still poses an issue because the accumulation of insulin in a particular area can result in glucose variability, including high and low blood sugars. This variability can increase insulin requirements (often unnecessarily), which implicates cost and potentially quality of life.

The good news is that avoiding the site can treat the issue, and proper site rotation and hygiene can often prevent it from occurring.

Person wearing an insulin pump
Carlo Prearo / EyeEm / Getty Images  

Lipohypertrophy Symptoms

Lipohypertrophy presents as the most common skin complication of diabetes. Additionally, there are less obvious symptoms of lipohypertrophy, such as a change in blood sugar control.

The physical symptoms of lipohypertrophy include swollen, hard, lumpy deposits of fat and scar tissue under the skin. The skin area may also feel firmer than other areas. These areas should not be warm or painful.

If someone with diabetes has lipohypertrophy and continues to inject insulin into the affected tissue or uses that site for an insulin pump or continuous glucose monitor, they can have erratic blood sugars due to changes in insulin absorption.

Blood sugar variability will depend on the amount and type of insulin used. For example, if someone is injecting long-acting insulin into an affected area, the insulin can remain at the site for longer periods of time, resulting in hyperglycemia. While the insulin remains in the site, it can further enhance lipohypertrophy.

Causes

People with diabetes who take insulin are at an increased risk of lipohypertrophy. A systematic review and meta-analysis suggest that around 38% (a number that varies depending on the study) of people with diabetes have lipohypertrophy.

There are several causes that can increase the risk of lipohypertrophy, but it is most common in people who receive multiple daily injections or those who wear insulin pumps or continuous glucose monitors and do not practice proper site rotation. Increasing doses of insulin and longer duration of insulin therapy also increased the risk of lipohypertrophy.

Repeated insulin injection into the same area and inability to space injections within the same site area is the most common cause of lipohypertrophy. Sometimes people with diabetes are unaware they are even doing this, while other people prefer to inject into these areas because it doesn't hurt as much as undamaged skin.

One study suggests that the type of insulin regimen you are on can also affect your risk of developing lipohypertrophy.

Needle reuse—using a needle multiple times without changing it—can also increase the risk of lipohypertrophy. In addition, people who are thinner may also be at increased risk because they have less surface area to inject insulin.

Diagnosis

Site lipohypertrophy can vary in size and shape—ranging from a small pea size to a tennis ball. An area of skin that has lipohypertrophy will usually be visually noticeable, though this is not always the case. In some instances, there is no lump at all and rather a harder patch of skin.

It is recommended that people who are caring for others with diabetes always check injection sites, especially if a person is noticing a change in blood sugar. Examination of injection sites through palpation and visual inspection often pinpoints the cause.

The newer insulin analogs can make these skin changes very subtle, so it is important to actually feel the area you use to inject or infuse insulin.

To assess this on your own, firmly stroke the areas in a sweeping motion to feel for any lumps. If a site is found, a healthcare provider can assist in navigating barriers as to why changing sites is problematic and educate you on proper technique.

Treatment

The main treatment is to avoid the affected area and rotate sites regularly. Changing needles after each injection is also necessary.

For those people who are using pumps or continuous glucose monitors, changing sites as prescribed is recommended. If you are using the buttocks, for example, and it's time to change your site, you should move the injection site a finger's length (about an inch) away from the last site. You can use a chart or a calendar to help you keep track.

Avoid the affected area until the skin has healed. If you are not sure if the skin has healed, ask a medical team to assess it for you.

If you are changing your site altogether, from the abdomen to the buttocks, for example, you may need to test your blood sugar more frequently as every site has different absorption rates and can affect blood sugar differently.

Coping

Aesthetically, lipohypertrophy can be unappealing, but the good news is that if it's caught early, the skin can heal and become smoother. Adjusting to new insulin sites can also be a bit overwhelming in the beginning.

Kimberly Avelin, age 27, who has been living with type 1 diabetes since she was 11 years old, gives us some inspiration. She says:

"Having diabetes means that some days are easier than others and unfortunately what works one day may not work the next, so it's important to celebrate the good days when you can. Diabetes doesn’t stop you from doing anything you want to do, it just takes a lot more planning."

If you are struggling with lipohypertrophy, be sure to get support. Contact a medical team for education, advice, and support.

Prevention

In the years Avelin has had diabetes, she has never knowingly experienced lipohypertrophy. Over the course of her journey, she has transitioned from multiple daily injections (averaging six-to-seven daily) to an insulin pump and continuous glucose monitor.

Her advice for avoiding lipohypertrophy is to be diligent about rotating sites and keeping them clean. Not only does she rotate the site of the body she uses, she rotates the position on the site regularly, too. She says:

"My pump site changes every three days and my sensor site every 10 days. I wear my continuous glucose monitor on the upper part of the glute and rotate sides every sensor session. For my pump, I rotate the infusion sites on different parts of the abdomen. I used to wear it on the upper part of the glute, opposite from where my sensor was, however, suddenly, the insulin absorption was not good there. Perhaps, now that I think about it, this was a sign of the beginnings of lipohypertrophy, although visually it looked fine."

Avelin's story demonstrates that even though she has had diabetes for many years, she never fully understood lipohypertrophy. Perhaps she never actually experienced it, but she wasn't 100% sure. Not until she was educated on the subject did she question if her change in blood glucose control was a result of this.

Her story also serves as a great example of being proactive when blood sugars change. Anytime there is a pattern when blood sugars start to rise unexpectedly for several days in a row without any other behavior changes (changes to eating, illness, changes to exercise), it's a good idea to evaluate your sites. When Avelin noticed a change in her blood sugars, she changed her site and saw a different result.

Oftentimes physicians or people with diabetes will think to increase insulin dosages right away, but simply changing your injection site can improve blood sugar control. In fact, in a study which examined 430 outpatients injecting insulin, 39.1% of people with lipohypertrophy had unexplained hypoglycemia and 49.1% glycemic variability compared with only 5.9% and 6.5%, respectively, in those without lipohypertrophy.

The Role of a Certified Diabetes Care and Education Specialist

Insulin injection technique is something that should be touched on regularly. Even if a person has had diabetes for a long time, injection technique can often be suboptimal.

Certified Diabetes Care and Education Specialists (CDCES) can educate people with diabetes on the proper injection technique and identify barriers as to why they continue to inject into the same spot.

If it is because of pain, a CDCES can assess the needle length and diameter and recommended a thinner and shorter needle, or they can demonstrate the proper injection technique and temperature at which insulin should be administered. For example, cold insulin may sting more and injecting with room temperature insulin is more comfortable.

A CDCES can detect other insulin injection errors which can implicate blood glucose control. For example, not holding long enough at the site may cause some insulin to leak out and result in an inaccurate insulin dose.

Additionally, they can provide people with diabetes with an insulin injection or infusion rotation schedule which shows them when to inject, where to inject, and which sites have the fastest verses slowest absorption rates.

A Word From Verywell

Lipohypertrophy is a common skin condition that affects people with diabetes who are taking insulin. Although it can cause glucose variability and be frustrating, it can be prevented and treated. Proper site rotation and spacing, injection technique, and use of new needles are all important in prevention.

If you are struggling with this skin condition, get support. Find a Certified Diabetes Care and Education Specialist who can give you the proper education and training you deserve.

6 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
  1. Xu X-H, Carvalho V, Wang X-H, Qiu S-H, Sun Z-L. Lipohypertrophy: prevalence, clinical consequence, and pathogenesisChinese Medical Journal. 2021;134(1):47-49. doi:10.1097/CM9.0000000000000970

  2. Deng N, Zhang X, Zhao F, Wang Y, He H. Prevalence of lipohypertrophy in insulin‐treated diabetes patients: A systematic review and meta‐analysis. J Diabetes Investig. 2018;9(3): 536–543. doi:10.1111/jdi.12742

  3. Pozzuoli GM, Laudato M, Barone M, Crisci F, Pozzuoli B. Errors in insulin treatment management and risk of lipohypertrophy. Acta Diabetol. 2018;55(1):67–73. doi:10.1007/s00592-017-1066-y

  4. Barola A, Tiwari P, Bhansali A, Grover S, Dayal D. Insulin-related lipohypertrophy: lipogenic action or tissue trauma? Front Endocrinol (Lausanne). 2018;9:638. doi:10.3389/fendo.2018.00638

  5. Teslik M. Lipohypertrophy: A forgotten problem. Association of Diabetes Care and Education Specialists.

  6. Blanco M, Hernadez MT, Strauss, KW, Amaya M. Prevalence and risk factors of lipohypertrophy in insulin-injecting patients with diabetes. Diabetes Metab. 2013;39(5):445–453. doi:10.1016/j.diabet.2013.05.006

By Barbie Cervoni MS, RD, CDCES, CDN
Barbie Cervoni MS, RD, CDCES, CDN, is a registered dietitian and certified diabetes care and education specialist.