Levemir (insulin detemir) is a brand-name prescription medication. It’s approved by the Food and Drug Administration (FDA) to improve blood sugar levels in:

Levemir is typically used as a long-term treatment to help manage blood sugar levels.

Here are some fast facts about Levemir:

Like other drugs, Levemir can cause side effects. Read on to learn about potential common, mild, and serious side effects. For a general overview of Levemir, including details about its uses, see this article.

Levemir can cause certain side effects, some of which are more common than others. These side effects may be temporary, lasting a few days to weeks. However, if the side effects last longer than that, bother you, or become severe, be sure to talk with your doctor or pharmacist.

These are just a few of the more common side effects reported by people who took Levemir in clinical trials:

* For more information about this side effect, see the “Side effect specifics” section below.

Mild side effects can occur with Levemir use. This list doesn’t include all possible mild side effects of the drug. For more information, you can refer to Levemir’s prescribing information.

Mild side effects that have been reported with Levemir include:

These side effects may be temporary, lasting a few days to weeks. But if the side effects last longer than that, bother you, or become severe, be sure to talk with your doctor or pharmacist.

Note: After the Food and Drug Administration (FDA) approves a drug, it tracks side effects of the medication. If you develop a side effect while taking Levemir and want to tell the FDA about it, visit MedWatch.

* For more information about this side effect, see the “Side effect specifics” section below.

Levemir may cause serious side effects in some people. The list below may not include all possible serious side effects of the drug. For more information, you can refer to Levemir’s prescribing information.

If you develop serious side effects while taking Levemir, call your doctor right away. If the side effects seem life threatening or you think you’re having a medical emergency, immediately call 911 or your local emergency number.

Serious side effects that have been reported and their symptoms include:

* For more information about this side effect, see the “Side effect specifics” section below.
† An allergic reaction is possible after using Levemir. But it’s not clear whether this side effect occurred in clinical trials.

Levemir may cause several side effects. Here are some frequently asked questions about the drug’s side effects and their answers.

I’m using the Levemir FlexTouch pen. Does this form of the drug cause any unique side effects?

No. The possible side effects of the Levemir vial and Levemir FlexTouch pens are the same.

Levemir is given as a subcutaneous injection, which means you inject it under your skin. Subcutaneous injections can increase your risk of certain side effects. These may include injection site reactions* and lipodystrophy (skin thickening, dents, lumps, or pits at the injection site).*

Note that Levemir previously came in a prefilled pen called Levemir FlexPen. Currently, the drug comes in vials or a prefilled Levemir FlexTouch pen. If you have questions about the different forms of Levemir, talk with your doctor.

* For more information about this side effect, see the “Side effect specifics” section below.

Do Levemir’s side effects include changes in mood?

Levemir shouldn’t cause changes in mood, sometimes called mood swings.

However, Levemir commonly causes hypoglycemia* (low blood sugar). Symptoms of mild hypoglycemia may include irritability, anxiety, or mood changes. Some studies found that people with diabetes have an increased risk of depression.

Mood-related symptoms of mild hypoglycemia are temporary. If your mood changes continue, talk with your doctor. They can help you identify other causes and discuss how to best manage this side effect.

* For more information about hypoglycemia, see the “Side effect specifics” section below.

Can Levemir’s side effects harm my kidneys?

Levemir should not harm the kidneys.

Kidney problems are common in people with diabetes, the condition that Levemir treats. Also, people with kidney problems may have an increased risk of hypoglycemia* (low blood sugar) while taking Levemir.

Your doctor may need to adjust your Levemir dose if you develop kidney problems from diabetes while taking the drug. They’ll also have you closely monitor your blood sugar levels at home to help prevent low blood sugar.

* For more information about hypoglycemia, see the “Side effect specifics” section below.

Learn more about some of the side effects that Levemir may cause.

Weight gain

Some people may have weight gain while taking Levemir. Weight gain is a common side effect of all types of insulin. And Levemir is a type of insulin.

Insulin can cause weight gain because of how it works. Insulin signals your body to move sugar out of your blood and into your cells. Once the sugar is inside the cells, your body can use it as energy. The body stores the sugar it does not use as fat, which can lead to weight gain.

In clinical trials, people with type 2 diabetes had slight weight gain while taking Levemir. People taking Levemir for type 1 diabetes reported minor weight gain and some had slight weight loss (less than a pound).

Also, weight changes during treatment with Levemir may be related to peripheral edema (swelling of the arms, hands, legs, or feet). Edema may cause your weight to increase or decrease.

What you can do

If you have diabetes, it’s important to maintain a weight that’s healthy for you. Significant weight gain can increase your blood sugar levels, making your diabetes more difficult to manage. Your doctor can give you advice on eating moderately and exercising regularly.

If you have weight gain while taking Levemir, talk with your doctor. They may need to adjust your dosage of Levemir or recommend other ways to manage your diabetes.

Skin thickening, dents, or lumps at the injection site

Lipodystrophy (skin thickening, dents, or lumps at the injection site) is a common side effect of Levemir treatment. It can occur due to changes in how your body stores fat under your skin.

Also, Levemir may cause hard lumps in the skin due to a side effect called localized cutaneous amyloidosis. This occurs due to a build-up of certain proteins under the skin.

These changes may occur at or around the areas where you inject Levemir. It’s important to avoid injecting Levemir into thickened, pitted, lumpy, or indented areas of your skin. Doing so could lead to your blood sugar levels becoming too high or too low.

What you can do

To help minimize or prevent these changes in your skin, inject each dose of Levemir into a slightly different site in the area you use. You can inject it under the skin of your upper arm, thigh, or abdomen. You shouldn’t inject Levemir into the same spot for every dose.

If you use two injections of Levemir or two different types of insulin, you may use the same area for both. But you should choose slightly different spots for each injection. For example, you can inject both doses under the skin of your left thigh but a few inches apart.

If you’re concerned about lipodystrophy while using Levemir, talk with your doctor. They may monitor you more closely during your treatment with Levemir.

Hypoglycemia

Hypoglycemia (low blood sugar) is a common side effect of Levemir. This was the most common side effect in clinical trials of the drug.

Slight decreases in blood sugar can cause mild symptoms. Symptoms of mild hypoglycemia may include:

If you do not receive treatment for hypoglycemia right away, symptoms may become serious and even life threatening. Symptoms of severe hypoglycemia (very low blood sugar levels) can include:

Certain medical conditions or other factors can increase your risk of hypoglycemia while taking Levemir. This includes taking Levemir in combination with certain other diabetes medications called sulfonylureas, such as glyburide (Diabeta), glipizide (Glucotrol), and glimepiride (Amaryl).

Additionally, eating or exercising more or less than usual can affect your blood sugar levels. So can weight changes. Since Levemir lowers blood sugar levels, these variables may increase your risk of hypoglycemia.

What you can do

To help prevent hypoglycemia, it’s best to follow your doctor’s instructions for checking your blood sugar levels at home. They’ll likely have you check your blood sugar more often in certain situations, such as:

  • after adjusting your dosage of Levemir or other medications
  • when you start a new medication
  • when you change your diet or exercise routine
  • if you become ill or do not eat as much as usual

If you have symptoms of hypoglycemia, you’ll need to raise your blood sugar level as soon as possible. You’ll do this by immediately eating or drinking a sugary food or beverage, such as a glucose tablet or a glass of fruit juice. Diet soda or diet or sugar-free candy will not treat hypoglycemia. Then, you should recheck your blood sugar levels.

Before starting Levemir, your doctor will go over what to do if you have severe hypoglycemia. Depending on how severe your symptoms are, you may need someone else to help you.

This is likely the case if your doctor prescribes glucagon (Gvoke) for you. It’s an injection used to treat severe episodes of hypoglycemia.

You (or someone helping you) should also call 911 or your local emergency number.

Reactions at the injection site

People taking Levemir may have reactions at the injection site. Levemir is a drug that you’ll inject under the skin of your thighs, upper arm, or abdomen.

It’s common to have mild symptoms that affect the skin where you inject Levemir. These may include:

What you can do

Injection site reactions from Levemir are usually mild and temporary. But there are ways to help prevent or minimize discomfort from Levemir injections.

Be sure to allow Levemir to come to room temperature before giving yourself a dose. Injections may feel more painful if you inject cold insulin you’ve just taken out of the refrigerator. (For more details about how to use and store Levemir, see this article.)

Also, be sure to rotate your injection sites. Do not inject your dose of Levemir into the same spot every time. Avoid injecting Levemir into areas where your skin is scarred, bruised, painful, or damaged.

In some cases, the symptoms of injection site reactions may be similar to an allergic reaction.* If you have a rash, hives, or itching that doesn’t go away or becomes severe, talk with your doctor right away. They will help determine if you’re having an allergic reaction and whether you should keep taking Levemir.

* For more information about allergic reactions while taking Levemir, see the “Allergic reaction” section below.

Allergic reaction

As with most drugs, Levemir can cause an allergic reaction in some people. But it’s not clear whether this side effect occurred in clinical trials.

Symptoms can be mild or serious and can include:

  • skin rash
  • itching
  • flushing
  • swelling under your skin, typically in your lips, eyelids, feet, or hands
  • swelling of your mouth, tongue, or throat, which can make it hard to breathe

What you can do

For mild symptoms of an allergic reaction, talk with your doctor right away. They may recommend ways to ease your symptoms and determine whether you should keep taking Levemir. But if your symptoms are serious and you think you’re having a medical emergency, immediately call 911 or your local emergency number.

Be sure to talk with your doctor about your health history before taking Levemir. This drug may not be the right treatment for you if you have certain medical conditions or other factors that affect your health. The conditions and factors to consider include:

Hypoglycemia. Do not take Levemir if you’re currently experiencing an episode of hypoglycemia (low blood sugar). Levemir lowers your blood sugar levels and will worsen hypoglycemia. This may be life threatening. Before starting Levemir, talk with your doctor about how to recognize and manage hypoglycemia.

Low potassium. Levemir can cause hypokalemia (low potassium levels in your blood). If you already have a condition or take certain medications that cause low potassium, taking Levemir could lower your potassium further. Because of this risk, your doctor may monitor your potassium levels regularly during your treatment with Levemir.

Kidney or liver problems. If you have kidney or liver problems, you may have a higher risk for hypoglycemia (low blood sugar) while taking Levemir. Because of this risk, your doctor may monitor you closely while you’re taking the drug. They may also adjust your dosage or have you check your blood sugar levels often.

Heart failure. If you have heart failure and take certain diabetes medications, Levemir may not suit you. These include a group of drugs called thiazolidinediones, such as pioglitazone (Actos) or rosiglitazone (Avandia). Taking this type of drug in combination with Levemir may worsen heart failure or make the symptoms of this condition, such as edema, more severe.

Allergic reaction. If you’ve had an allergic reaction to Levemir or any of its ingredients, your doctor will likely not prescribe Levemir. Ask your doctor what other medications may be better options for you.

Alcohol use with Levemir

Alcohol isn’t known to interact with Levemir. However, drinking alcohol too much or too often can make your diabetes more difficult to manage. This is because alcohol can raise or lower your blood sugar levels. And Levemir is used to reduce blood sugar levels in people with diabetes.

If you drink alcohol, talk with your doctor about how much is safe to drink while taking Levemir.

Pregnancy and breastfeeding while taking Levemir

Levemir is safe to use while pregnant. In clinical trials, Levemir was studied in pregnant females* with type 1 diabetes. The results did not increase the risk of harm to the fetus.

Doctors commonly prescribe insulin, including Levemir, to people with diabetes during pregnancy.

It is unknown if Levemir is safe to use while breastfeeding. It’s known that insulins, including Levemir, pass into breast milk. But, it’s not known whether or how it could affect a breastfed child, including whether it could cause side effects.

If you’re pregnant, breastfeeding, or planning either, talk with your doctor. They may adjust your Levemir dosage or monitor you more carefully during this time.

* Sex and gender exist on spectrums. Use of the term “female” in this article refers to sex assigned at birth.

Levemir may cause mild or serious side effects. The drug’s more common side effects are usually easy to manage. When you start taking Levemir, your doctor or pharmacist will explain how to recognize and manage its side effects.

If you’d like to learn more about Levemir, talk with your doctor or pharmacist. They can help answer any questions you have about side effects of taking the drug.

Besides talking with your doctor, you can do some research on your own. These articles might help:

  • More information about Levemir. For details about other aspects of Levemir, refer to this article.
  • Dosage specifics. To learn about Levemir’s dosage, see this article.
  • Drug comparison. To learn how Levemir compares with Lantus, read this article.
  • A look at diabetes. For details about your condition, see our diabetes hub, as well as this list of related articles.

Disclaimer: Medical News Today has made every effort to make certain that all information is factually correct, comprehensive, and up to date. However, this article should not be used as a substitute for the knowledge and expertise of a licensed healthcare professional. You should always consult your doctor or another healthcare professional before taking any medication. The drug information contained herein is subject to change and is not intended to cover all possible uses, directions, precautions, warnings, drug interactions, allergic reactions, or adverse effects. The absence of warnings or other information for a given drug does not indicate that the drug or drug combination is safe, effective, or appropriate for all patients or all specific uses.