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

Humalog is a prescription medication that’s used to help manage blood sugar in people with diabetes. There are two types of Humalog product: Humalog and Humalog Mix. Both types can be used in adults with type 1 or type 2 diabetes. Humalog can also be used in certain children with type 1 diabetes.

Humalog is a rapid-acting insulin. You’ll receive it by injection under your skin. (You can give yourself injections after your doctor shows you how.) Healthcare professionals in a hospital may sometimes give Humalog by intravenous (IV) infusion (an injection into your vein that’s given over time).

Humalog comes in these forms.

  • disposable injection pens (Humalog, Junior, and Tempo)
  • The disposables are used with the disposables with the disposables with the disposables with the disposables with the disposables with the disposables with the disposables with the disposables with the disposables with the disposables with the disposables with the disposables with the disposables with
  • There are devices that can give extra doses of insulin and also inject it under your skin.

Humalog mix is a combination of rapid-acting and intermediate-acting Insulin. Humalog Mix will be injected under your skin. After your doctor shows you how to do it, you can give yourself injections. Humalog Mix is in these forms.

  • disposable injection pens
  • The vials are used with theinsulin syringes.

For more information about Humalog, see this in-depth article on the drug.

Humalog can cause mild or serious side effects. These are also referred to as adverse effects. Continue reading to learn more.

“Some people may experience side effects during their treatment. Humalog’s more commonly reported side effects may include:”

See the side effects explained below for more information.

There are some mild side effects that have been reported with Humalog.

See the side effects explained below for more information.

These side effects should be temporary. Some may be easy to manage. If you have any symptoms that bother you, talk to your doctor or pharmacist. Humalog should be used unless your doctor recommends it.

Humalog may cause mild side effects other than the ones listed above. For details, see the patient information for the different forms: Humalog U-100, Humalog KwikPen U-200, Humalog Mix75/25, and Humalog Mix50/50.

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 Humalog, visit MedWatch.

There have been serious side effects reported with Humalog.

See the side effects explained below for more information.

If you develop serious side effects, you should call your doctor. If the side effects seem life threatening or if you think you have a medical emergency, immediately call the emergency number.

There are many questions about Humalog.

Are the side effects of Humalog KwikPen different from those of other forms of Humalog?

“Humalog shouldn’t have different side effects.”

Humalog and Humalog mix are the two types of product. Both come in different forms.

Humalog comes as:

  • disposable injection pens (Humalog, Junior, and Tempo)
  • The disposables are used with the disposables with the disposables with the disposables with the disposables with the disposables with the disposables with the disposables with the disposables with the disposables with the disposables with the disposables with the disposables with the disposables with
  • The vials are used with theinsulin syringes. or insulin pumps (devices that continuously inject insulin under your skin and can also give extra doses at mealtimes)

Humalog mix comes as:

  • disposable injection pens
  • The vials are used with theinsulin syringes.

There are examples of possible side effects with Humalog, see “What are the mild side effects of Humalog?” and “What are the serious side effects of Humalog?”

How do Humalog’s side effects compare with those of Lantus?

Humalog and Lantus are different types of insulin. Humalog contains insulin lispro, while Lantus contains insulin glargine. Both products can cause very similar side effects. For examples, see “What are the mild side effects of Humalog?” and “What are the serious side effects of Humalog?” above.

The main difference between Humalog and Lantus is that Humalog is rapid acting, while Lantus is long acting.

Humalog starts working in 15 minutes and lasts for about 4 hours. It’s used to help manage surges of blood sugar at mealtimes. Lantus doesn’t start working for a couple of hours, but it lasts for 24 hours or longer. It’s used to help provide steady background management of your blood sugar throughout the day.

Both products can cause low blood sugar levels. But because of their different profiles, this can happen at different times with each product.

“Humalog can help you with your blood sugar levels if you don’t eat a meal. It is possible to have low blood sugar levels after taking Lantus. If you exercised more than you planned, it could happen.”

If you have questions about the differences between the two types ofinsulin, talk to your doctor or pharmacist.

What should I do if I notice thickening skin on my stomach where I inject Humalog?

Humalog can cause skin changes in the area where you have it.

The fat under your skin can become fat if it is not removed. dents or pits can develop in your skin if you have thin of the fat tissue. See the side effects explained below for more information about these skin changes.

“Humalog can make the problem worse by injecting it into the skin. The body won’t be able to absorb theinsulin It won’t manage your blood sugar as usual.”

If you notice that your stomach is getting bigger, stop taking Humalog there. There is no skin thickness on your stomach. Change the injection site every time to prevent skin growth.

“Humalog can be injected into your thighs, buttocks, and upper arms if there aren’t any places on your stomach that aren’t skinnier. Humalog won’t work as quickly if you’re aware that it’s absorbed into your body more slowly. If you are concerned about injecting Humalog in a place other than your stomach, talk to a healthcare professional.”

“If you don’t inject the skin will go away on its own. If these changes are bothering you, talk to your doctor.”

What side effects might occur if I switch from Humalog to Novolog?

Humalog and Novolog contain different types ofinsulin. Humalog and Novolog contain the same amount of the drug. Both products can cause side effects. The examples are of the mild side effects of Humalog and the serious side effects of Humalog.

SwIt was itching. from one insulin product to another could affect your blood sugar management for a time. For example, it could cause you to have high or low blood sugar levels.

If your doctor recommends swIt was itching. from Humalog to Novolog, you’ll need to monitor your blood sugar more frequently for a while after the change. Your doctor will help you adjust your new insulin regimen based on your blood sugar levels.

Are the side effects of Humalog, Humalog Mix75/25, and Humalog Mix50/50 different?

Humalog has side effects that are different from Humalog Mix. There are two ways to see what the side effects of Humalog are.

“Humalog doesn’t last as long as Humalog Mix. Humalog is a rapid-acting form of the drug that works in about 15 minutes. Humalog mix is a combination of rapid-acting and intermediate-acting Insulin. It takes about 15 minutes to start working and 22 hours to finish.”

Both products can cause low blood sugar levels. It is possible to have low blood sugar levels several hours after taking Humalog Mix. If you exercised more than you planned, this could happen.

If you have questions about the products, you can talk to your doctor or pharmacist.

Can Humalog cause heart-related side effects?

Humalog can cause heart-related side effects.

If you have low blood sugar levels with Humalog, this can cause The heart is racing.. This may feel like your heart is pounding, racing, fluttering, or skipping beats. To read more about low blood sugar levels with Humalog, see “Side effects explained” below.

More rarely, Humalog can cause hypokalemia, which is a low potassium level in your blood. Hypokalemia can cause an irregular heart rate. If your heart feels like it’s beating irregularly while you’re receiving Humalog, contact your doctor. You may need a blood test to check your potassium level.

If you use Humalog with a type of diabetes drug called thiazolidinediones, this might in rare cases cause or worsen heart failure. Examples of thiazolidinediones include Avandia (rosiglitazone) and Actos (pioglitazone). If you use Humalog with one of these drugs, contact your doctor right away if you have symptoms of heart failure. These may include:

  • It is swelling of your feet.
  • sudden weight gain
  • The breath was very thin.

If you have questions about Humalog, you should talk to your doctor.

Can Humalog cause diarrhea?

Yes. As with other insulins, some people who use Humalog may have diarrhea. It’s worth noting that diarrhea is common in people with diabetes, but it’s not clear what the reason for this is.

If you experience frequent scurvy while using Humalog, contact your doctor. They can look into what is causing this side effect and suggest ways to manage it.

Some of the side effects Humalog may cause are discussed.

Swelling in your hands and feet

Humalog can sometimes cause peripheral edema, which is swelling in your hands, feet, or ankles caused by fluid retention. This type of swelling is one of the more common side effects of all insulin products, including Humalog.

Swelling in your feet and ankles can also be caused by problems related to diabetes, such as problems with blood circulation, your kidneys, or your heart.

What might help

If you have swelling of your feet, there are some tips you can use.

  • Raise your feet on a cushion.
  • Wear compression socks to help improve blood flow.
  • Exercise frequently.
  • “Don’t sit for long periods of time.”
  • Drink lots of fluids to help keep fluid out of your body.

“If these tips don’t help you with your swelling, you should talk to your doctor.”

If you have swollen ankles or feet and you’re using Humalog with a type of diabetes drug called thiazolidinediones, contact your doctor immediately. Examples of these drugs include Avandia (rosiglitazone) and Actos (pioglitazone). Swollen ankles, The breath was very thin., or sudden weight gain could be symptoms of heart failure. This condition can be a problem with this combination of drugs.

Low blood sugar levels

Humalog, like all insulin products, can sometimes cause low blood sugar levels. The medical term for this is hypoglycemia. It’s one of the most common side effects of Humalog.

Humalog can cause low blood sugar levels.

If low blood sugar levels are not treated, they can quickly become serious or life threatening. Your own symptoms may change over time, so note that.

Symptoms of hypoglycemic condition may include:

A person can appear drunk if they have low blood sugar levels. They may include:

Very low blood sugar levels can lead to seizures or coma, and even death.

What might help

If you have low blood sugar levels, you need to eat or drink something that will quickly get absorbed by your body. Examples include:

  • There are tablets or gels ofglucose.
  • Fruit juice or soda is not diet or sugar-free.
  • Jellybeans or candy.

Talk to your doctor about ways to treat low blood sugar levels during Humalog treatment.

Injection site reactions and lipodystrophy

You might have a reaction after receiving Humalog. You may have swelling, redness, or tenderness in the area where you have the injection. These symptoms usually go away in a few days.

You might also notice a bit of redness after your injection. If you accidentally catch a tiny blood vessel under the skin with the injection, this can happen. It is usually nothing to worry about.

As with other insulin products, long-term use of Humalog injections can also commonly cause skin changes called lipodystrophy. With lipodystrophy, you may have thickening of the fatty tissue under your skin. These areas may feel hard, rubbery, or lumpy. You may also have thinning of this fatty tissue, which can lead to dents or pits developing in your skin.

Humalog can cause a build up of the substance under your skin. This is a disease on the skin. It can cause a lump under your skin.

If you inject Humalog into areas with hardening, thickening, or lumps, the medication might not be correctly absorbed into your body. This can make Humalog less effective than usual at managing your blood sugar levels. On the other hand, if you inject Humalog into areas with pitting or dents, the medication can be more easily absorbed into your body. And this can raise your risk for low blood sugar levels (see “Low blood sugar levels” above).

What might help

It is important to use a different injection site each time you use Humalog. This is a rotating injection site.

“If you notice any changes in your skin, don’t use Humalog in those areas. Don’t inject into areas that are damaged or tender.”

“If you don’t inject in the affected area, it will get better. It may take a while.”

If you have skin changes that are not going away, talk to your doctor.

Weight gain

It is possible to gain weight while using Humalog. Excess sugar in your blood is stored as fat in your body because of the effects of the drug,insulin.

What might help

Talk to your doctor about how to keep a moderate weight during Humalog treatment. Humalog is meant to be used with a balanced diet and regular exercise. Your doctor can help you with an eating and exercise plan. They can help you with your weight.

If you suddenly gain a lot of weight and you’re using Humalog with a type of diabetes drug called thiazolidinediones, contact your doctor right away. Examples of this type of drug include Avandia (rosiglitazone) and Actos (pioglitazone). Sudden weight gain, swollen ankles, or The breath was very thin. could be symptoms of heart failure. This condition can be a problem with this combination of drugs.

Allergic reaction

Humalog can cause an allergic reaction in some people. An allergic reaction is caused by your immune system.

Mild or serious symptoms can be present.

  • skin There is a rash.
  • It is itchy.
  • flushing (temporary warmth, redness, or deepening of skin color)
  • “It’s swelling under your skin, usually in your lips, hands, or feet.”
  • It can be hard to breathe if you have swelling of your mouth, tongue, or throat.

What might help

If you have mild symptoms of an allergic reaction, such as a mild There is a 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). They may also recommend a product you apply to your skin, such as hydrocortisone cream.

If your doctor confirms you had a mild allergic reaction to Humalog, they will decide if you should keep using it.

If you have a severe allergic reaction, you should call the emergency number. These symptoms could be life threatening and need immediate medical care.

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

Keeping track of side effects

Keep notes on any side effects you have during your treatment. You can share this information with your doctor. This is helpful when you are starting to use a combination of treatments.

Side effect notes can include things.

  • What dose of drug did you use when you had a side effect?
  • How soon after starting that dose did you experience side effects?
  • What were your symptoms after the side effect?
  • How did it affect your daily activities?
  • What other drugs were you using?
  • Other information is important to you.

Sharing notes with your doctor will help him learn more about Humalog. If needed, your doctor can use this information to adjust your treatment plan.

If you have a medical condition that affects your health, Humalog may not be right for you. Before using Humalog, you should talk to your doctor about your health history. The list has factors to consider.

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

Low blood sugar levels. Humalog can cause and worsen low blood sugar levels. If you frequently have low blood sugar levels, discuss this with your doctor before you start receiving Humalog. If you’re having an episode of low blood sugar, don’t use Humalog because the drug will make it worse. Severe low blood sugar levels could be life threatening. To learn more, see “Side effects explained” above.

Kidney or liver problems. If you have a kidney or liver problem, you’re more likely to have low blood sugar levels with Humalog. Talk with your doctor about ways to avoid this.

Low potassium level. If you have a low level of potassium in your blood, using Humalog could make this worse. If you have low potassium, or you’re at risk for this problem, your doctor may monitor your potassium level while you receive Humalog. You might be at risk for low potassium if you take certain other medications with Humalog. Examples include corticosteroids and certain diuretics.

Heart failure. If you have heart failure and you take a type of diabetes drug called thiazolidinediones, using Humalog as well could make your heart failure worse. Ask your doctor if Humalog is right for you. Examples of thiazolidinediones include Actos (pioglitazone) and Avandia (rosiglitazone).

Alcohol use and Humalog

Humalog can raise your risk for low blood sugar levels. If you drink alcohol, talk to your doctor about how much you can safely drink. If you drink alcohol with Humalog, your doctor may suggest that you check your blood sugar more often.

Pregnancy and breastfeeding while using Humalog

There haven’t been enough studies to know for sure if Humalog is safe to use during pregnancy. But studies do show that it doesn’t seem to increase the risk of pregnancy loss or problems with fetal development (commonly known as birth defects).

If diabetes isn’t managed well in pregnancy, this can have serious risks for both the pregnant person and the fetus. The American Diabetes Association recommends managing diabetes with insulin during pregnancy.

If you are pregnant or planning to become pregnant, you should talk to your doctor about the best way to manage your diabetes.

“Humalog is generally safe to use during breastfeeding. When it is taken by mouth, it can’t be absorbed. If a child is breastfed, it can’t absorb theinsulin that gets into breast milk.”

“Humalog may cause similar side effects, but they aren’t many that they can cause. They are usually mild, even though they can be common.”

Serious side effects such as low blood sugar levels and lipodystrophy can usually be avoided by carefully managing your diabetes. This involves having a clear plan for doses, as well as diet and exercise, and regularly rotating your injection sites.

It’s important to remember that Humalog is used to help manage mealtime surges of blood sugar. You’ll typically use it with a longer acting insulin that provides background control of your blood sugar over the day.

If you’re starting insulin treatment and your doctor recommends Humalog, you may have more questions about side effects. You may also have questions about side effects if your doctor recommends swIt was itching. to Humalog from a different type of insulin.

Some questions you might want to ask your doctor.

  • Humalog injections are not hurt.
  • Is Humalog riskier than other drugs?
  • Is Humalog more likely to cause low blood sugar levels, injection site reactions, and lipodystrophy if I use it with aninsulin pump?
  • Do my other diabetes treatments increase my risk for side effects?
  • Can other conditions increase my risk for Humalog side effects?

If you have type 2 diabetes, check out Healthline’s online newsletter for tips on managing your condition.

Q:

Can other drugs increase my risk for side effects?

Anonymous

A:

Your risk for low blood sugar can increase if you take Humalog with certain other medications. Examples include other non-insulin medications to treat diabetes, salicylates such as aspirin, antibiotics, certain antidepressant medications, and blood pressure medications.

Inform your doctor about any medications you are taking. If you are already taking Humalog, you should talk to your doctor or pharmacist about any new medications.

The Healthline Pharmacist TeamAnswers represent the opinions of our medical experts. All content is strictly informational and should not be considered medical advice.

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.