Lipohypertrophy is a lump of fatty tissue under your skin caused by repeated injections in the same place. It’s common in people with diabetes. Lipohypertrophy can affect your body’s ability to absorb insulin and cause serious complications. It’s important to rotate injection or pump sites, inspect the skin and use a new needle for each injection.


What is lipohypertrophy?

Repeated injections in the same area cause lipohypertrophy, which involves a lump of fatty tissue under your skin. The area may feel lumpy, firm or rubbery. It also may be somewhat numb.


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Who might get lipohypertrophy?

Lipohypertrophy is common among people who need regular insulin injections or infusion to treat diabetes. It can also affect people who need medication injections for HIV.

Factors that increase your risk include:

  • Failing to rotate or change injection or infusion (pump) sites regularly.
  • Having a low body mass index (BMI).
  • Reusing needles (they should only be used once).
  • Using human insulin instead of analog insulin (created in a laboratory).

How common is lipohypertrophy?

The condition is common in people with diabetes, affecting as many as 64% of this population at some point.


How does lipohypertrophy affect my body?

In addition to causing lumps, the condition can affect the way your body absorbs insulin. Insulin is a hormone that regulates metabolism and treats diabetes.

If you inject or infuse insulin into an area with lipohypertrophy, the insulin might be absorbed more slowly or quickly than expected. This may cause:

Even if you’re taking steps to manage diabetes, you may have trouble controlling it because of lipohypertrophy.

Symptoms and Causes

What causes lipohypertrophy?

Lipohypertrophy occurs when a person injects insulin or another medication into the same patch of skin too many times. This includes infusion through insulin pumps.

The repeat injections can cause a buildup of fat, protein and scar tissue. Plus, lipohypertrophic fat cells are about twice the size of normal fat cells, which can make the lumps even larger.


What does lipohypertrophy look like and feel like?

Lipohypertrophy often occurs in the thigh or belly, which are common sites for injections. They vary in size from a golf ball to a fist. They may look or feel:

  • Firmer or harder than surrounding tissue.
  • Lumpy.
  • Raised.
  • Rubbery.
  • Swollen.
  • Thicker than the skin in that area used to feel.

In addition, lipohypertrophic lumps often have less feeling or sensation. Because the areas may be numb or somewhat numb, many people prefer to use those areas for injections to reduce pain. But this can worsen the lumps and diabetes.

Does lipohypertrophy spread?

Lipohypertrophy doesn’t spread, but a lump can get bigger over time if injections continue in that spot. And new lumps can appear in other places on your body that receive frequent injections.

Diagnosis and Tests

How is lipohypertrophy diagnosed?

Early detection is key to identifying the problem, reversing it and preventing complications. You can identify lipohypertrophy by inspecting your skin regularly, especially before you insert a needle or pump cannula (tiny hollow tube that insulin flows through).

Also, ask your healthcare provider to inspect your injection sites each time you visit. Your healthcare provider can diagnose lipohypertrophy by simply:

  • Looking at the lump.
  • Pressing on the area.
  • Talking to you about your injection and pump site habits.

Management and Treatment

How is lipohypertrophy treated?

There isn’t a specific treatment for lipohypertrophy. You should stop injections in that area for at least two to three months until the area heals and returns to normal.

A type of plastic surgery called liposuction also may be considered to remove severe fat deposits. Surgical removal may also be considered for areas that don’t resolve or are bothersome.


How can I reduce my risk of lipohypertrophy?

Several strategies can help you prevent lipohypertrophy:

  • Change injection sites each time, and pump sites every two to three days.
  • Don’t reuse needles.
  • Establish a plan that includes a schedule of specific injection or pump sites, then stick to it.
  • Have your healthcare provider inspect your injection or pump sites every time you have in-person appointments.
  • Inspect your skin before injecting medication or inserting a pump cannula to look for any tissue that looks or feels different.
  • Keep track of where you inject medications or place your pump using a chart, calendar or app.
  • Space injection sites at least a finger width apart (three finger widths for pumps).

Outlook / Prognosis

Does lipohypertrophy go away?

Lipohypertrophic skin can heal. It often takes months, sometimes years. You shouldn’t inject any medications into the area until it heals.

Does lipohypertrophy come back?

The condition can come back in the same area or another site. This is more likely to happen if you don’t rotate injection or pump sites frequently or if you reuse needles.

Living With

How do I take care of myself?

If you have an area on your skin that might be lipohypertrophy, stop injecting into that site. Even if an injection is going to hurt more in another area, you should change the injection or pump site. Repeated injections or infusion into a lipohypertrophic area can worsen the lump, interfere with insulin absorption and lead to complications.

When should I seek medical attention?

Talk to your healthcare provider about any skin irregularities, especially if you’re having trouble controlling your blood sugar.

Lipohypertrophic skin shouldn’t be:

  • Hot or warm to the touch.
  • Red.
  • Bruised.
  • Painful.

If you experience any of these symptoms, seek medical attention. It might be a sign of infection or another problem.

A note from Cleveland Clinic

Repeated injections in the same area cause lipohypertrophy, a lump of fatty tissue under your skin. If you need regular insulin injections for diabetes or another medication, you should change the injection or pump site regularly. Talk to your healthcare provider if you have any concerns about your skin.

Medically Reviewed

Last reviewed by a Cleveland Clinic medical professional on 04/29/2022.

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