If you have diabetes, your doctor may suggest NovoLog as a treatment option for you. It’s a type of fast-acting insulin used to manage blood sugar levels in adults and children with type 1 or type 2 diabetes.

Diabetes is a condition that causes high blood sugar. If not treated, high blood sugar levels can lead to problems in other parts of your body, such as your heart, kidneys, and nerves.

NovoLog basics

NovoLog contains the active ingredient insulin aspart. (An active ingredient is what makes a drug work.) NovoLog belongs to a group of medications called fast-acting insulins.

NovoLog is a type of biologic medication. A biologic is made from parts of living organisms. NovoLog is not available in a biosimilar form. (Biosimilars are like generic drugs. But unlike generics, which are made for non-biologic drugs, biosimilars are made for biologic drugs.)

Keep reading to learn more about NovoLog, including how it compares to other insulins, answers to some frequently asked questions, and more.

NovoLog comes as a solution that’s typically given as a subcutaneous injection (under the skin). It’s available in three forms:

  • NovoLog FlexPen, a disposable, prefilled insulin pen
    • NovoLog FlexTouch was a prefilled pen that has been replaced by NovoLog FlexPen
  • NovoLog PenFill, cartridges that are used with a reusable insulin pen
  • NovoLog vial that’s used with syringes or an insulin pump

In some cases, your doctor may use the vial form of NovoLog to give the drug as an intravenous (IV) infusion. You may receive NovoLog this way if you’re getting treatment in a hospital.

To use NovoLog insulin pens, you’ll attach a pen needle before each injection. For more information about NovoLog’s forms or the supplies you’ll need, see the drug manufacturer’s website. You can also talk with your doctor or pharmacist.

NovoLog and HumaLog are both fast-acting insulins prescribed for people with diabetes. They have similar dosages, side effects, and forms.

To learn more, see this detailed comparison of NovoLog and Humalog. Also, talk with your doctor or pharmacist about the treatment option that’s right for you.

Find answers to some commonly asked questions about NovoLog.

How does NovoLog compare vs. Novolin, Fiasp, Basaglar, and insulin lispro?

NovoLog, Novolin, Fiasp, Basaglar, and insulin lispro are all insulins used to treat diabetes.

NovoLog and Fiasp are both fast-acting insulins. They both contain insulin aspart. But Fiasp also contains niacinamide (vitamin B3), which is meant to help Fiasp start working faster than NovoLog.

Novolin is considered a regular insulin (also called short-acting insulin), and Basaglar is a type of long-acting insulin (also called basal insulin).

Your doctor may prescribe other insulins to use with NovoLog, such as a long-acting insulin. An example of a long-acting insulin is Basaglar. But they won’t prescribe another fast-acting insulin with NovoLog.

To learn more about how these medications are alike and different, talk with your doctor or pharmacist.

What type of insulin is NovoLog? Is it a long-acting or fast-acting insulin?

NovoLog is a type of fast-acting insulin. Fast-acting insulins are used before a meal to manage blood sugar after you eat.

To learn more about the different types of insulin, check out this article. You can also talk with your doctor or pharmacist.

Is NovoLog the same as Humalog?

NovoLog isn’t the same as Humalog, but the drugs have some similarities. To learn more, see the “What should I know about NovoLog vs. HumaLog?” section above.

What’s the peak time for NovoLog?

Novolog has its peak effects about 1 to 3 hours after injection. But keep in mind this time can vary from person to person.

If you have questions about when NovoLog will have its peak effect for you, talk with your doctor or pharmacist.

Does Novolog need to be refrigerated? When does the drug expire after it’s been opened?

Before being opened, Novolog may be refrigerated or kept at room temperature. But it’s important to note that the drug’s storage affects how soon it expires.

  • When stored unopened at room temperature, Novolog is good for up to 28 days.
  • When stored unopened in the refrigerator, Novolog is good until the expiration date on the box.

Once you’ve opened a NovoLog pen, keep it at room temperature (up to 86o F or 30o C). You shouldn’t put it back in the refrigerator. Be sure to use NovoLog within 28 days of opening it.

If you’re using NovoLog vials, these may either be stored at room temperature or refrigerated after opening.

If you have other questions about how to store NovoLog, talk with your doctor or pharmacist.

How does NovoLog work? And what’s its half-life?

NovoLog’s mechanism of action (how it works) is to mimic the job of natural insulin, a hormone that’s meant to keep your blood sugar levels within a healthy range.

If you have diabetes, your body doesn’t make insulin or can’t use it properly. Like natural insulin, NovoLog tells your body to move sugar out of your blood and into your body’s cells. This lowers your blood sugar level.

A drug’s half-life is the amount of time it takes for your body to get rid of half a dose. NovoLog’s half-life is about 81 minutes. The drug’s effects usually last 3 to 5 hours, but this can vary. NovoLog stays in your system for up to 7 hours after your last dose.

Like most drugs, NovoLog may cause mild or serious side effects. The lists below describe some of the more common side effects that NovoLog may cause. These lists don’t include all possible side effects.

Keep in mind that your risk of side effects from a drug can depend on:

  • your age
  • other health conditions you have
  • other medications you take

Your doctor or pharmacist can tell you more about the potential side effects of NovoLog. They can also suggest ways to help reduce side effects.

Mild side effects

Here’s a short list of some of the mild side effects that NovoLog can cause. To learn about other mild side effects, talk with your doctor or pharmacist, or read NovoLog’s prescribing information.

Mild side effects of NovoLog that have been reported include:

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

Mild side effects of many drugs may go away within a few days to a couple of weeks. But if they become bothersome, talk with your doctor or pharmacist.

Serious side effects

Serious side effects from NovoLog can occur, but they aren’t common. If you have serious side effects from NovoLog, call your doctor right away. But if you think you’re having a medical emergency, you should call 911 or your local emergency number.

Serious side effects of NovoLog that have been reported include:

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

Side effect focus

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

Weight gain

Treatment with NovoLog can cause weight gain in some people. It’s not known how common weight gain was in NovoLog’s studies.

Weight gain is a side effect of all insulins, and it’s related to how insulin works in your body.

All insulins (including NovoLog) remove excess sugar from your blood. Some of this sugar is used by your body’s cells for energy. But some sugar gets stored as fat to be used for energy later. This can lead to weight gain over time.

What might help

If you’re concerned about weight gain during your NovoLog treatment, talk with your doctor.

If you use NovoLog and also take a type of diabetes drug called a thiazolidinedione, you should call your doctor right away if you suddenly gain a lot of weight (such as 5 pounds overnight). Sudden weight gain can be a symptom of heart failure. In rare cases, taking NovoLog and thiazolidinedione drugs together can lead to heart failure.

Low blood sugar

As with all medications used to treat diabetes, NovoLog can cause hypoglycemia (low blood sugar). This is the most common side effect caused by drugs that contain insulin, including NovoLog. (The active drug in NovoLog is insulin aspart.) In most cases, this side effect is mild.

Symptoms of mild hypoglycemia can include:

  • weakness
  • confusion
  • hunger
  • feeling dizzy or jittery
  • headache

In rare cases, NovoLog can cause severe hypoglycemia (extremely low blood sugar). Your risk of severe hypoglycemia from NovoLog may be higher if you:

  • are fasting
  • take other diabetes drugs with Novolog
  • have kidney or liver problems

Symptoms of severe hypoglycemia may include:

Severe hypoglycemia is a medical emergency that requires help from another person. If not treated quickly, it can lead to fainting, coma, seizures, or even death. If you have symptoms of severe hypoglycemia, you or someone around you should call 911 or your local emergency number. Or you should go to the nearest emergency room.

If you’re concerned about your risk of severe hypoglycemia with NovoLog, talk with your doctor.

What might help

Before you begin taking NovoLog, talk with your doctor about checking your blood sugar during your treatment. Your doctor will let you know how often you’ll need to do this.

You should also talk with your doctor about what to do if you experience hypoglycemia during your NovoLog treatment. In many cases, mild hypoglycemia can be treated at home using fast-acting carbohydrates, such as:

  • glucose (sugar) tablets
  • 1 tablespoon of honey
  • ½ cup of juice or regular (non-diet) soda
  • three or four pieces of hard candy

Your doctor may also prescribe glucagon (GlucaGen) for you, which is a medication used to quickly raise blood sugar levels that are severely low. If your doctor prescribes glucagon for you, they’ll tell you more about the dosage and how it’s used.

Before starting treatment with NovoLog, talk with your doctor about your treatment plan in case you have hypoglycemia. But if you have symptoms of severe hypoglycemia or symptoms that feel life threatening, you or someone around you should call 911 (or your local emergency number). Or go to the closest emergency room.

Injection site reactions

You may have reactions at the injection site after taking a dose of NovoLog. In studies, this was a common side effect in people using NovoLog.

Injection-site reactions may include:

  • itchiness
  • skin discoloration
  • pain
  • swelling

In some cases, NovoLog injections can also cause lipodystrophy (skin dimpling). With this condition, your skin thickens or forms “pits” at the site where you inject NovoLog.

If NovoLog (or other insulin) is injected into skin areas affected by lipodystrophy, the drug may not work properly. This could lead to your blood sugar becoming too high or too low.

What might help

It’s recommended that you rotate injection sites each time you use NovoLog. This will lower your risk for injection site reactions and lipodystrophy.

You should also avoid injecting NovoLog anywhere that your skin is:

  • thickened
  • pitted or has lumps
  • bruised
  • hard
  • scaly
  • tender
  • damaged in any way

If you experience lipodystrophy or injection site reactions that are bothersome to you, talk with your doctor. They may recommend other treatment options for your diabetes.

Allergic reaction

Some people may have an allergic reaction to NovoLog. It’s not known how often these reactions occurred in studies, but they’re thought to be rare.

Symptoms of a mild allergic reaction can include:

A more severe allergic reaction is rare but possible. Symptoms of a severe allergic reaction can include swelling under your skin, typically in your eyelids, lips, hands, or feet. They can also include swelling of your tongue, mouth, or throat, which can cause trouble breathing.

Call your doctor right away if you have an allergic reaction to NovoLog. But if you think you’re having a medical emergency, call 911 or your local emergency number.

Prices of prescription drugs can vary depending on many factors. These factors include what your insurance plan covers and which pharmacy you use.

Keep in mind that pen costs and vial costs may vary. Also, NovoLog’s cost with insurance will depend on your specific health insurance plan.

You’ll also need other supplies to use NovoLog, such as insulin syringes, pen needles, an insulin pump, or a reusable insulin pen device. These supplies are sold or dispensed separately, and their cost can vary.

If you have questions about how to pay for your prescription, talk with your doctor or pharmacist. You can also visit the NovoLog manufacturer’s website to see if they have support options.

You can also check out this article to learn more about saving money on prescriptions.

Your doctor will recommend the dosage of NovoLog that’s right for you. Below are commonly used dosages, but always take the dosage your doctor prescribes.

Forms

Novolog is available in three forms:

  • NovoLog FlexPen, a disposable, prefilled insulin pen
  • NovoLog PenFill, cartridges that are used with a reusable insulin pen
  • NovoLog vial that’s used with syringes or an insulin pump

In some cases, your doctor may use the vial form of NovoLog to give the drug as an intravenous (IV) infusion. You may receive NovoLog this way if you’re getting treatment in a hospital.

To use NovoLog, you’ll need supplies, such as insulin syringes, pen needles, an insulin pump, or a reusable insulin pen device. These supplies are sold or dispensed separately. Your doctor or pharmacist can tell you more about these.

Recommended dosage

The recommended dosage of NovoLog is to inject a dose 5 to 10 minutes before eating a meal.

If you’re using NovoLog with an insulin pump, talk with your doctor about your dosage. They’ll go over the instructions with you.

There’s no dosage calculator available from NovoLog’s manufacturer, but it does provide these details on how dosages are calculated.

Questions about NovoLog’s dosage

Below are some common questions about NovoLog’s dosage.

  • What if I miss a dose of NovoLog? Novolog should be taken 5 to 10 minutes before a meal. If you forget until after you start eating, you can take your dose mid-meal. But if you remember after the meal, you should check your blood sugar level to determine if you need a dose of NovoLog. If you aren’t sure what to do, ask your doctor or pharmacist for advice. To help make sure you don’t miss a dose, be sure to take NovoLog with you when you’ll be away from home for a meal. You may also want to try a medication reminder such as setting an alarm or downloading a reminder app.
  • Will I need to use NovoLog long term? You’ll likely use NovoLog long term, if you and your doctor agree that it’s safe and working well for you.
  • How long does NovoLog take to work? NovoLog begins working about 5 to 10 minutes after injecting a dose. That’s why you’ll take it 5 to 10 minutes before eating a meal.

Your doctor will explain how you should take NovoLog. They will also explain how much to take and how often. Be sure to follow your doctor’s instructions.

Using NovoLog

Novolog is available in the following forms:

  • NovoLog FlexPen, a disposable, prefilled insulin pen
  • NovoLog PenFill, cartridges that are used with a reusable insulin pen
  • NovoLog vial that’s used with syringes or an insulin pump

You’ll give yourself NovoLog as an injection under the skin. For step-by-step instructions on how to use the NovoLog FlexPen, see the drug manufacturer’s website. You can also view the drug’s prescribing information.

In some cases, your doctor may use the vial form of NovoLog to give the drug as an intravenous (IV) infusion. You may receive Novolog through this route of administration if you’re getting treatment in a hospital.

Accessible medication containers and labels

If it’s hard for you to read the label on your prescription, tell your doctor or pharmacist. Certain pharmacies may provide medication labels that:

  • have large print
  • use braille
  • contain a code you can scan with a smartphone to change the text into audio

Your doctor or pharmacist may be able to recommend a pharmacy that offers these options if your current pharmacy doesn’t.

Using NovoLog with other drugs

You’ll likely use NovoLog with other drugs to treat diabetes. This may include other insulins, such as Novolin (insulin human). It may also include diabetes drugs you take by mouth, such as metformin (Glucophage).

Your doctor will let you know whether you’ll use NovoLog with other drugs.

Questions about using NovoLog

Below are some common questions about using NovoLog.

  • Should I take NovoLog with food? You’ll give yourself a dose of NovoLog just before eating a meal.
  • Should I still take Novolog if I skip a meal? No. If you skip a meal due to illness or another reason, you should also skip that dose. Remember that Novolog is a mealtime insulin that’s fast-acting. If you inject a dose and do not start eating within 5 to 10 minutes, your blood sugar may become too low.
Questions for your doctor

You may have questions about NovoLog and your treatment plan. It’s important to discuss all your concerns with your doctor.

Here are a few tips that might help guide your discussion:

  • Before your appointment, write down questions such as:
    • How will NovoLog affect my body, mood, or lifestyle?
  • Bring someone with you to your appointment if doing so will help you feel more comfortable.
  • If you don’t understand something related to your condition or treatment, ask your doctor to explain it to you.

Remember, your doctor and other healthcare professionals are available to help you. And they want you to get the best care possible. So, don’t be afraid to ask questions or offer feedback on your treatment.

NovoLog and Admelog are both fast-acting insulins used in people with diabetes. They have very similar side effects, dosages, and forms.

To learn more about these drugs, check out this side-by-side comparison. You can also talk with your doctor to find out if one of these treatment options is right for you.

NovoLog is used to manage blood sugar levels in adults and children with type 1 or type 2 diabetes.

Diabetes is a condition that causes high blood sugar. If not treated, high blood sugar can lead to problems in other parts of your body, including your eyes, feet, kidneys, and nerves.

With type 1 diabetes, cells in your pancreas that make insulin are destroyed. This means your body can’t make its own insulin. Type 1 diabetes is a type of autoimmune disease. This type of diabetes develops very quickly, and its cause is not fully understood.

With type 2 diabetes, your body stops responding to insulin. Eventually, your body may also stop making its own insulin. Type 2 diabetes is believed to be caused by several factors, including genetics, your weight, and your diet.

NovoLog works by moving sugar out of your blood and into your cells, which use the sugar for energy.

You shouldn’t use more NovoLog than your doctor prescribes. Using more than this can lead to serious side effects.

Symptoms of overdose

Symptoms caused by an overdose can include:

  • low blood sugar, which can be severe and can cause confusion, dizziness, or fainting
  • low potassium level, which can cause symptoms such as constipation, muscle cramps, and weakness

What to do in case you take too much NovoLog

Call your doctor if you think you’ve taken too much NovoLog. You can also call 800-222-1222 to reach the American Association of Poison Control Centers or use its online resource. But if you have severe symptoms, immediately call 911 or your local emergency number. Or go to the nearest emergency room.

There are important considerations to discuss with your doctor before you start taking NovoLog. These include your overall health and any medical conditions you may have.

You should also tell your doctor about all medications you may take.

Interactions

Taking a medication with certain vaccines, foods, and other things can affect how the medication works. These effects are called interactions.

Before taking NovoLog, be sure to tell your doctor about all medications you take, including prescription and over-the-counter types. Also describe any vitamins, herbs, or supplements you use. Your doctor or pharmacist can tell you about any interactions these products may cause with NovoLog.

Interactions with drugs or supplements

NovoLog can interact with several types of drugs. These include:

This list does not contain all types of drugs that may interact with NovoLog. Your doctor or pharmacist can tell you more about these interactions and any others that may occur with use of NovoLog.

Warnings

NovoLog 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 take NovoLog. Factors to consider include those in the list below.

  • Heart failure. If you have heart failure, tell your doctor before you begin treatment with NovoLog. Using NovoLog with certain diabetes drugs called thiazolidinediones can worsen heart failure. Your doctor can determine the safest treatment plan for you if you have heart failure.
  • Kidney or liver problems. If you have kidney or liver problems, you may have a higher risk of low blood sugar with NovoLog. Talk with your doctor about whether NovoLog is safe for you to take. If they decide to prescribe NovoLog for you, they may have you take a lower dose. They may also ask you to check your blood sugar levels more often.
  • Allergic reaction. If you’ve had an allergic reaction to NovoLog or any of its ingredients, your doctor will likely not prescribe NovoLog. Ask them what other medications are better options for you.

NovoLog and alcohol

It’s best to avoid or limit alcohol use during your Novolog treatment. Alcohol can affect your blood sugar levels, which could make NovoLog less effective. It can also raise your risk of certain side effects from NovoLog, including low blood sugar, diarrhea, and headache.

If you drink alcohol, talk with your doctor about the amount (if any) that may be safe to consume during your Novolog treatment.

Pregnancy and breastfeeding

It isn’t known whether it’s safe to take NovoLog while pregnant. But it’s also important to note that uncontrolled diabetes can cause problems during pregnancy.

If you’re pregnant or planning to become pregnant, talk with your doctor about the best treatments for your diabetes during pregnancy.

It’s not known if NovoLog passes into breast milk or whether it could cause side effects in a breastfed child. If you’re currently breastfeeding or planning to do so, talk with your doctor about your options.

If you have type 1 or type 2 diabetes, you may benefit from using NovoLog.

If you’re interested in learning more about using NovoLog to manage your blood sugar, talk with your doctor. You can ask them about the risks and benefits of using this drug for your condition. Here are a few questions you can ask:

  • How often should I check my blood sugar while using NovoLog?
  • Will I need to keep taking my other diabetes medications if I use NovoLog?
  • What should I expect when starting treatment with NovoLog?
  • How often will I need lab work done during my NovoLog treatment?

You may be interested in learning more about diabetes medications.

You can also find support and advice from the Bezzy T2Dcommunity, as well as from the Healthline diabetes newsletter.

Q:

Will I need a prescription for pen needles to use with the NovoLog FlexPen?

Anonymous

A:

It depends on where you live. The pen needles that you’ll use with the FlexPen (such as NovoFine or NovoTwist needles) are sold or dispensed separately from the drug. Some states require a prescription for pen needles and others don’t.

Regardless of your state’s requirements, most insurance plans will cover pen needles if your doctor writes a prescription for them. This may lower the amount you have to pay.

For more information about pen needles or the supplies you’ll need to use other forms of NovoLog, talk with your doctor or pharmacist.

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

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