If you have diabetes, your doctor might suggest Levemir (insulin detemir) as a treatment option for you. Along with other questions you may have about the drug, you could be wondering about its side effects.

Levemir is a prescription long-acting insulin that’s used to treat type 1 and type 2 diabetes in adults and children ages 2 years and above.

For more information about Levemir, see this in-depth article.

Like other drugs, Levemir can cause mild or serious side effects. These side effects may be short term or long-lasting. Keep reading to learn more about possible side effects of the drug.

Some people may experience mild or serious side effects during their Levemir treatment. Examples of Levemir’s commonly reported side effects include:

* To learn more about this side effect, see the “Side effects explained” section below.

These aren’t all the side effects Levemir may cause. Continue reading to learn about other possible side effects of Levemir.

Levemir may cause some mild side effects. Examples of mild side effects that have been reported with Levemir include:

* To learn more about this side effect, see the “Side effects explained” section below.

In most cases, these side effects should be temporary. And some may be easily managed. But if you have any symptoms that are ongoing or that bother you, talk with your doctor or pharmacist. And don’t stop using Levemir without discussing it with your doctor first.

Levemir may cause mild side effects other than the ones listed above. See the Levemir prescribing information for details.

Note: After the Food and Drug Administration (FDA) approves a drug, it tracks side effects of the medication. If you’d like to notify the FDA about a side effect you’ve had with Levemir, visit MedWatch.

Serious side effects that have been reported with Levemir include:

* To learn more about this side effect, see the “Side effects explained” section below.
† An allergic reaction is possible after using Levemir. But it’s not clear whether this side effect occurred in studies.

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

Below are answers to some frequently asked questions about Levemir’s side effects.

Can Levemir cause kidney-related side effects?

No, there haven’t been reports of kidney-related side effects in studies of Levemir. But if you have serious kidney disease, let your doctor know before starting treatment with Levemir. Serious kidney problems can change the amount of Levemir in your bloodstream.

Based on how your kidneys are working, your doctor may adjust your Levemir dosage. They’ll also let you know if you need to monitor your blood sugar more often.

If you have kidney problems, you may have a higher risk of low blood sugar levels during Levemir treatment. Your doctor may have you monitor your blood sugar more often if they prescribe Levemir to you.

Are there side effects specific to the Levemir FlexTouch pen?

No, there aren’t any. Side effects are similar for the two forms of Levemir: prefilled FlexTouch pens* and vials filled with liquid for injection by syringe.

There are several advantages to using the FlexTouch pen instead of a regular syringe to inject Levemir. The FlexTouch pen uses a simple push-button injection to deliver your dose of insulin.

If you have questions about the FlexTouch pen and possible side effects, talk with your doctor or pharmacist.

* The Levemir FlexTouch pen replaced the Levemir FlexPen, which used a different technology to deliver insulin.

Are mood changes a side effect of Levemir?

No, Levemir isn’t known to cause mood changes, also referred to as mood swings. In studies of the drug, mood changes weren’t reported as a side effect.

But Levemir may cause severe low blood sugar. This condition can result in mood changes, such as anxiety, irritability, or nervousness. Studies also show that people with diabetes have a higher risk of depression.

If you’re concerned about mood changes, talk with your doctor. They can tell you more about causes of mood changes with diabetes and how you can manage your symptoms.

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

Weight gain

Levemir may cause weight gain. This is a common side effect of all forms of insulin. Studies have shown that Levemir can cause small weight increases in people with type 1 or type 2 diabetes. But it causes less weight gain than other types of long-acting insulin.

What might help

If you have weight gain while using Levemir and you’re concerned, talk with your doctor. They can suggest ways to manage your weight, such as moderate exercise and eating a healthful diet.

Keep in mind that big changes in your weight may require adjustments to your Levemir dosage. Your doctor will monitor your blood sugar levels and make changes to your dosage if needed.

Headache

Headache is a common side effect of Levemir. If you have migraine or a history of headaches, let your doctor know. Your doctor can help you decide if Levemir is the right treatment option for you.

What might help

If you have a mild headache with Levemir, your doctor may suggest taking an over-the-counter (OTC) pain reliever such as Tylenol (acetaminophen) or Advil (ibuprofen). Be sure to talk with them first before taking any OTC medications.

If you’re having serious headaches, contact your doctor right away. They can discuss with you whether Levemir is safe for you to use long term.

Swelling in the arms or legs

Levemir can cause fluid buildup in your arms or legs. This can result in swelling in the arms or legs, or other areas of the body.

Using Levemir with certain diabetes medications, specifically thiazolidinediones (TZDs), can increase your risk of this side effect. In rare cases, this combination has caused new or worsening heart failure. Examples of TZDs include Actos (pioglitazone) and Avandia (rosiglitazone).

What might help

Before starting treatment with Levemir, tell your doctor or pharmacist about all medications you’re taking, particularly any for diabetes. They’ll check for drug interactions with Levemir.

If you experience mild swelling in your legs, arms, or other areas of your body, talk with your doctor. They can suggest ways to help ease this side effect, such as lowering your salt intake or exercising. In some cases, your doctor may suggest taking a diuretic medication (water pill) to reduce the swelling.

If the problem is serious, your doctor may suggest a medication other than Levemir to manage your diabetes. They can give you more information based on your condition.

Changes to the skin near an injection site

Using injectable insulin such as Levemir for a long time can cause changes to the skin near an injection site. This is referred to as lipodystrophy. The skin may become thicker, pitted, or thinner from repeated injections to the same area.

This side effect is possible because Levemir can cause changes to fat cells under your skin.

What might help

To lower your risk of developing such skin changes near an injection site, it’s important to rotate injection sites. This means injecting Levemir in a different area of your body each time you give yourself a dose. (You can inject the drug into your thigh, upper arm, or belly.)

It’s not recommended to inject Levemir in an area with thickened or pitted skin. If you do, you may not get the full benefits of your dose. You also should avoid injecting Levemir into skin that’s damaged, bruised, scaly, or scarred.

Your doctor or pharmacist can show you the best way to inject Levemir. They can also tell you how often to rotate injection sites to minimize the risk of skin changes.

Low blood sugar

Mild low blood sugar is a common side effect of insulin drugs, including Levemir. In studies, most people who used Levemir had low blood sugar that was mild at least once.

Less commonly, insulin drugs such as Levemir can also cause severe low blood sugar, which is a serious side effect. The risk of this side effect is higher if you’re taking certain other medications to manage your diabetes.

Symptoms of severe low blood sugar include:

What might help

It’s important to regularly monitor your blood sugar levels while you’re taking Levemir. This can help you avoid sudden serious changes in your blood sugar levels. You should also try to eat healthy meals regularly throughout the day.

If you have a sudden drop in blood sugar, consume glucose tablets or 15 grams of carbohydrates. This can help boost blood sugar levels quickly.

Ask your doctor about steps you can take to treat low blood sugar while using Levemir.

If you have symptoms of a severe drop in blood sugar as listed above, call 911 or get emergency medical help right away.

Allergic reaction

Like most drugs, Levemir can cause an allergic reaction in some people.

Symptoms can be mild or serious and can include:

  • skin rash
  • itchiness
  • flushing (temporary warmth, redness, or deepening of skin color)
  • swelling under your skin, typically in your eyelids, lips, hands, or feet
  • swelling of your mouth, tongue, or throat, which can make it hard to breathe

What might help

If you have mild symptoms of an allergic reaction, such as a mild rash, call your doctor right away. To manage your symptoms, they may suggest an over-the-counter antihistamine you take by mouth, such as Benadryl (diphenhydramine). Or they may recommend a product you apply to your skin, such as hydrocortisone cream.

If your doctor confirms you had a mild allergic reaction to Levemir, they’ll decide if you should continue using it.

If you have symptoms of a severe allergic reaction, such as swelling or trouble breathing, call 911 or your local emergency number right away. These symptoms could be life threatening and require immediate medical care.

If your doctor confirms you had a serious allergic reaction to Levemir, they may have you switch to a different treatment.

Keeping track of side effects

During your Levemir treatment, consider keeping notes on any side effects you’re having. Then, you can share this information with your doctor. This is especially helpful to do when you first start taking new drugs or using a combination of treatments.

Your side effect notes can include things such as:

  • what dose of drug you were taking when you had the side effect
  • how soon after starting that dose you had the side effect
  • what your symptoms were from the side effect
  • how it affected your daily activities
  • what other medications you were also taking
  • any other information you feel is important

Keeping notes and sharing them with your doctor will help your doctor learn more about how Levemir affects you. And your doctor can use this information to adjust your treatment plan if needed.

Levemir may not be right for you if you have certain medical conditions or other factors that affect your health. Talk with your doctor about your health history before you use Levemir. The list below includes factors to consider.

Kidney problems. Problems with your kidneys can result in a higher amount of Levemir in your bloodstream than is typical. If you have a history of kidney disease, tell your doctor. They’ll monitor your blood sugar levels and adjust your dosage if needed.

Allergic reaction. If you’ve had an allergic reaction to Levemir or any of its ingredients, your doctor won’t prescribe Levemir. Ask your doctor what other medications are better options for you.

Liver problems. Problems with your liver can result in a higher level of Levemir in your bloodstream than is typical. Your doctor will monitor your blood sugar levels and make changes to your dosage if needed to reduce any harmful effects.

Alcohol use and Levemir

There are no reports of interactions between alcohol and Levemir in studies of the drug. But drinking alcohol can lower your blood sugar levels. Drinking alcohol while using Levemir may also increase your risk of severe low blood sugar.

If you plan to drink alcohol while taking Levemir, ask your doctor what amount is safe for you to consume.

Pregnancy and breastfeeding while taking Levemir

Studies have shown Levemir to be safe for use during pregnancy. Diabetes during pregnancy can increase your risk of serious health complications, including the risk of pregnancy loss.

If you’re using Levemir and plan to become pregnant, ask your doctor for more information about the safety and risks of Levemir. They can tell you more about Levemir use and any dosage changes you may need to make during pregnancy.

Levemir and other types of insulin have been found in breast milk. But there are no reports in studies of Levemir that the drug caused harmful effects to breastfed children.

If you plan to breastfeed during Levemir treatment, talk with your doctor. They can tell you more about the safety of Levemir while breastfeeding.

Your doctor may suggest Levemir as an option for treating your diabetes. But you may want information about its side effects to help you decide if this drug is right for you.

Levemir’s side effects may be short term or long-lasting. Before prescribing Levemir, your doctor will discuss the side effects of the drug. Ask them for more information about any side effects that concern you. Here are a few questions you might consider asking your doctor:

  • Will I have a higher risk of side effects from Levemir if I take it without food?
  • Is Levemir safe for me to take if I have migraine?
  • Would my risk of side effects from Levemir increase if I’m also taking other diabetes medications?

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Disclaimer: Healthline 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.