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Insulin Aspart (rDNA Origin) Injection

pronounced as (in' su lin) (as' part)

Why is this medication prescribed?

Insulin aspart is used to treat type 1 diabetes (condition in which the body does not produce insulin and therefore cannot control the amount of sugar in the blood) in adults and children. It is also used to treat people with type 2 diabetes (condition in which the body does not use insulin normally and therefore cannot control the amount of sugar in the blood) who need insulin to control their diabetes. In patients with type 1 diabetes, insulin aspart is usually used with another type of insulin, unless it is used in an external insulin pump. In patients with type 2 diabetes, insulin aspart also may be used with another type of insulin or with oral medication(s) for diabetes. Insulin aspart is a short-acting, manmade version of human insulin. Insulin aspart works by replacing the insulin that is normally produced by the body and by helping move sugar from the blood into other body tissues where it is used for energy. It also stops the liver from producing more sugar.

Over time, people who have diabetes and high blood sugar can develop serious or life-threatening complications, including heart disease, stroke, kidney problems, nerve damage, and eye problems. Using medication(s), making lifestyle changes (e.g., diet, exercise, quitting smoking), and regularly checking your blood sugar may help to manage your diabetes and improve your health. This therapy may also decrease your chances of having a heart attack, stroke, or other diabetes-related complications such as kidney failure, nerve damage (numb, cold legs or feet; decreased sexual ability in men and women), eye problems, including changes or loss of vision, or gum disease. Your doctor and other healthcare providers will talk to you about the best way to manage your diabetes.

How should this medicine be used?

Insulin aspart comes as a solution (liquid; Fiasp, NovoLog) and a suspension (liquid with particles that will settle on standing; NovoLog Mix 70/30) to inject subcutaneously (under the skin). Insulin aspart solution (NovoLog) is usually injected 5–10 minutes before eating a meal. If you are using insulin aspart suspension (NovoLog Mix 70/30) to treat type 1 diabetes, it is usually injected within 15 minutes before a meal. If you are using insulin aspart suspension to treat type 2 diabetes, it is usually injected within 15 minutes before or after a meal. Insulin aspart solution (Fiasp) is usually injected at the start of a meal or within 20 minutes after starting a meal. Your doctor will tell you how many times you should inject insulin aspart each day. Follow the directions on your prescription label carefully, and ask your doctor or pharmacist to explain any part you do not understand. Use insulin aspart exactly as directed. Do not use more or less of it or use it more often than prescribed by your doctor.

Insulin aspart solution (Fiasp, NovoLog) may also be injected intravenously (into a vein) by a doctor or nurse in a healthcare setting. A doctor or nurse will carefully monitor you for side effects.

Never use insulin aspart when you have symptoms of hypoglycemia (low blood sugar) or if you have checked your blood sugar and found it to be low.

Insulin aspart controls diabetes but does not cure it. Continue to use insulin aspart even if you feel well. Do not stop using insulin aspart without talking to your doctor. Do not switch to another brand or type of insulin or change the dose of any type of insulin you are using without talking to your doctor. Always check the insulin label to make sure you received the right type of insulin from the pharmacy.

Insulin aspart comes in vials, cartridges that contain medication and are to be placed in dosing pens, and dosing pens that contain cartridges of medication. Be sure you know what type of container your insulin aspart comes in and what other supplies, such as needles, syringes, or pens, you will need to inject your medication.

If your insulin aspart comes in vials, you will need to use syringes to inject your dose. Ask your doctor or pharmacist to show you how to inject insulin aspart using a syringe. Ask your doctor or pharmacist if you have questions about the type of syringe you should use.

If your insulin aspart comes in cartridges, you will need to buy an insulin pen separately. Check the manufacturer's information for the patient to see what type of pen is right for the cartridge size you are using. Carefully read the instructions that come with your pen, and ask your doctor or pharmacist to show you how to use it. Ask your doctor or pharmacist if you have questions about the type of pen you should use.

If your insulin aspart comes in pens, be sure to read and understand the manufacturer's instructions. If you are blind or have poor eyesight, do not use this pen without help. Ask your doctor or pharmacist to show you how to use the pen. Follow the directions carefully, and always prime the pen before use.

Never reuse needles or syringes and never share needles, syringes, cartridges, or pens. If you are using an insulin pen, always remove the needle right after you inject your dose. Discard needles and syringes in a puncture-resistant container. Ask your doctor or pharmacist how to dispose of the puncture-resistant container.

Your doctor may tell you to mix your insulin aspart solution with another type of insulin (NPH insulin) in the same syringe. Your doctor will tell you exactly how to do this. Always draw insulin aspart into the syringe first, always use the same brand of syringe, and always inject the insulin immediately after mixing. Insulin aspart solution should not be mixed with insulin preparations other than NPH insulin. Insulin aspart suspension should not be mixed with any other insulin preparations.

Your doctor may tell you to dilute insulin aspart before injection to allow easier measurement of your dose. Your doctor will tell you exactly how to do this.

You can inject your insulin aspart in your thighs, stomach, upper arms, or buttocks. Never inject insulin aspart into a muscle. Change (rotate) the injection site within the chosen area with each dose; try to avoid injecting the same site more often than once every 1–2 weeks. Do not inject where the skin is thick, lumpy, tender, bruised, scaly, hard, or into areas of skin where there are scars or skin is damaged.

Always look at your insulin aspart before you inject it. If you are using insulin aspart solution, the insulin should be clear and colorless. Do not use this type of insulin aspart if it is colored, cloudy, thickened, or contains solid particles. If you are using insulin aspart suspension, the insulin should appear cloudy or milky after you mix it. Do not use this type of insulin if there are clumps in the liquid or if there are solid white particles sticking to the bottom or walls of the bottle. Do not use any type of insulin after the expiration date printed on the bottle has passed.

Insulin aspart suspension must be rolled gently between your hands to mix before use. Do not shake insulin aspart suspension. Ask your doctor or pharmacist if the type of insulin you are using should be mixed and how you should mix it if necessary.

Insulin aspart solution also can be used with an external insulin pump. Before using insulin aspart in a pump system, read the pump label to make sure the pump can be used for continuous delivery of fast-acting insulin. Read the pump manual for recommended reservoir and tubing sets, and ask your doctor or pharmacist to show you how to use the insulin pump. Do not dilute insulin aspart or mix it with any other type of insulin when using it in an external insulin pump. When using insulin aspart with an external insulin pump, replace the insulin in the reservoir at least every 6 days (Fiasp), at least every 7 days (Novolog), or according to the pump manual, whichever is shorter. Talk to your doctor or pharmacist about when you should change the infusion set and infusion set insertion site. If the infusion site is red, itchy, or thickened, tell your doctor and use a different infusion site.

When using insulin apart solution in an external insulin pump, high blood sugar may occur quickly if the pump stops working properly or if the insulin in the pump reservoir is exposed to direct sunlight or temperatures greater than 98.6°F (37°C). High blood sugar may also occur if the tubing leaks or becomes blocked, disconnected, or kinks. If the problem cannot be found quickly and corrected, call your doctor right away. You may need to temporarily use insulin by subcutaneous injection (using syringes or an insulin pen). Make sure you have back-up insulin and any necessary supplies on hand, and ask your doctor or pharmacist to show you how to use them.

Ask your pharmacist or doctor for a copy of the manufacturer's information for the patient.

Other uses for this medicine

This medication may be prescribed for other uses; ask your doctor or pharmacist for more information.

What special precautions should I follow?

Before using insulin aspart,

  • tell your doctor and pharmacist if you are allergic to insulin (Humulin, Novolin, others), any of the ingredients of insulin aspart, or any other medications. Ask your pharmacist or check the manufacturer's patient information for a list of the ingredients.
  • tell your doctor and pharmacist what prescription and nonprescription medications, vitamins, nutritional supplements, and herbal products you are taking. Your doctor may need to change the doses of your medications or monitor you carefully for side effects.
  • The following nonprescription or herbal products may interact with insulin aspart injection: Aspirin or magnesium salicylate (Doans, others). Be sure to let your doctor and pharmacist know that you are using these medications before you start using insulin aspart injection. Do not start these medications while using insulin aspart injection without discussing with your healthcare provider.
  • tell your doctor if you have vision problems or if you have or have ever had nerve damage caused by your diabetes; heart failure; or if you have any other medical conditions, including heart, kidney, or liver disease.
  • tell your doctor if you are pregnant, plan to become pregnant, or are breastfeeding. If you become pregnant while using insulin aspart, call your doctor.
  • if you are having surgery, including dental surgery, tell the doctor or dentist that you are using insulin aspart.
  • alcohol may cause a change in blood sugar. Ask your doctor about the safe use of alcoholic beverages while you are using insulin aspart.
  • ask your doctor what to do if you get sick, experience unusual stress, or change your diet, exercise, or activity schedule. These changes can affect your dosing schedule and the amount of insulin you will need.
  • ask your doctor how often you should check your blood sugar. Be aware that hypoglycemia may affect your ability to perform tasks such as driving and ask your doctor if you need to check your blood sugar before driving or operating machinery.

What special dietary instructions should I follow?

Be sure to follow all exercise and dietary recommendations made by your doctor or dietitian. It is important to eat a healthful diet, and to eat about the same amounts of the same kinds of food at about the same times each day. Skipping or delaying meals or changing the amount or kind of food you eat can cause problems with your blood sugar control.

What should I do if I forget a dose?

Insulin aspart must be injected shortly before or after a meal. If you remember your dose before or shortly after your meal, inject the missed dose right away. If some time has passed since your meal, follow the instructions provided by your doctor or call your doctor to find out whether you should inject the missed dose. Do not inject a double dose to make up for a missed one.

What side effects can this medication cause?

This medication may cause changes in your blood sugar. You should know the symptoms of low and high blood sugar and what to do if you have these symptoms.

Insulin aspart may cause side effects. Tell your doctor if any of these symptoms are severe or do not go away:

  • redness, swelling, or itching at the site of the injection
  • changes in the feel of your skin, skin thickening (fat build-up), lumps in the skin, or a little depression in the skin (fat breakdown)
  • weight gain

Some side effects can be serious. If you experience any of these symptoms, call your doctor immediately or get emergency treatment:

  • rash and/or itching over the whole body
  • shortness of breath
  • wheezing
  • dizziness
  • blurred vision
  • fast heartbeat
  • sweating
  • weakness, fatigue, constipation, muscle cramps, or abnormal heartbeat
  • large weight gain in a short period of time
  • swelling of the arms, hands, feet, ankles, or lower legs

Insulin aspart may cause other side effects. Call your doctor if you have any unusual problems while using this medication.

If you experience a serious side effect, you or your doctor may send a report to the Food and Drug Administration's (FDA) MedWatch Adverse Event Reporting program online ( or by phone (1-800-332-1088).

What should I know about storage and disposal of this medication?

Keep this medication in the container it came in and out of reach of children. Store unopened insulin aspart vials, cartridges, and pens in the refrigerator, but do not freeze them. Unopened refrigerated insulin aspart can be stored until the date shown on the company's label. If a refrigerator is unavailable (for example, when on vacation), store the unopened vials, cartridges, or pens at room temperature and away from direct sunlight and extreme heat. Unrefrigerated unopened vials, cartridges, and pens of insulin aspart solution (Fiasp, NovoLog) can be used within 28 days, but after that time they must be discarded. Unrefrigerated unopened vials of insulin aspart suspension (NovoLog 70/30) can be used within 28 days and unrefrigerated, unopened pens can be used within 14 days; after that time they must be discarded.

Opened vials of insulin aspart solution (Fiasp, Novolog) can be stored for 28 days at room temperature or in the refrigerator. If your doctor tells you to dilute your insulin aspart (Novolog), the vial of diluted medication can be stored for up to 28 days in the refrigerator or at room temperature. Opened insulin aspart solution (Novolog) cartridges and pens may be stored at room temperature for up to 28 days; do not refrigerate them. Opened pens containing NovoLog Mix 70/30 may be stored at room temperature for up to 14 days; do not refrigerate them. Opened insulin aspart solution (Fiasp) pens can be stored at room temperature or in the refrigerator for up to 28 days. Discard any insulin aspart product that has been exposed to extreme heat or cold.

It is important to keep all medication out of sight and reach of children as many containers (such as weekly pill minders and those for eye drops, creams, patches, and inhalers) are not child-resistant and young children can open them easily. To protect young children from poisoning, always lock safety caps and immediately place the medication in a safe location – one that is up and away and out of their sight and reach.

Unneeded medications should be disposed of in special ways to ensure that pets, children, and other people cannot consume them. However, you should not flush this medication down the toilet. Instead, the best way to dispose of your medication is through a medicine take-back program. Talk to your pharmacist or contact your local garbage/recycling department to learn about take-back programs in your community. See the FDA's Safe Disposal of Medicines website ( for more information if you do not have access to a take-back program.

In case of emergency/overdose

In case of overdose, call the poison control helpline at 1-800-222-1222. Information is also available online at If the victim has collapsed, had a seizure, has trouble breathing, or can't be awakened, immediately call emergency services at 911.

Insulin aspart overdose can occur if you use too much insulin aspart or if you use the right amount of insulin aspart but eat less than usual or exercise more than usual. Insulin aspart overdose can cause hypoglycemia. If you have symptoms of hypoglycemia, follow your doctor's instructions for what you should do if you develop hypoglycemia. Other symptoms of overdose:

  • loss of consciousness
  • seizures

What other information should I know?

Keep all appointments with your doctor and the laboratory. Your blood sugar and glycosylated hemoglobin (HbA1c) should be checked regularly to determine your response to insulin aspart. Your doctor will also tell you how to check your response to this medication by measuring your blood sugar levels at home. Follow these instructions carefully.

You should always wear a diabetic identification bracelet to be sure you get proper treatment in an emergency.

Do not let anyone else use your medication. Ask your pharmacist any questions you have about refilling your prescription.

It is important for you to keep a written list of all of the prescription and nonprescription (over-the-counter) medicines you are taking, as well as any products such as vitamins, minerals, or other dietary supplements. You should bring this list with you each time you visit a doctor or if you are admitted to a hospital. It is also important information to carry with you in case of emergencies.

Brand names

  • Fiasp®
  • NovoLog®
  • NovoLog® Mix 70/30
  • Ryzodeg® 70/30 (as a combination product containing Insulin Aspart and Insulin Degludec)
Last Revised - 08/15/2023