Fiasp (insulin aspart) is a brand-name medication prescribed to help manage blood sugar levels in adults and children with diabetes. As with other drugs, Fiasp can cause side effects, such as low blood sugar.

Fiasp 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 Fiasp in clinical trials:

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

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

Mild side effects that people using Fiasp have reported include:

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.

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 Fiasp and want to tell the FDA about it, visit MedWatch.

* For more information about this side effect, see “Side effect specifics” below.
† An allergic reaction is possible after using Fiasp. To learn more, see the “Side effect specifics” section below.

Fiasp may cause serious side effects, but they aren’t common. The list below may not include all possible serious side effects of the drug. For more information, you can refer to Fiasp’s prescribing information.

If you develop serious side effects while taking Fiasp, 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 and their symptoms that people using Fiasp have reported include:

* For more information about this side effect, see “Side effect specifics” below.
† An allergic reaction is possible after using Fiasp. To learn more, see the “Side effect specifics” section below.

Fiasp is approved to help manage blood sugar levels in children with diabetes. The side effects in children are similar to those seen in adults. Common side effects of Fiasp in children include:

  • runny nose
  • hypoglycemia
  • headache
  • fever
  • injection site reactions
  • upper respiratory tract infection
  • flu

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

How do side effects of Fiasp compare with those seen with NovoLog?

Fiasp and Novolog are both fast-acting insulins that contain the same active ingredient (insulin aspart). This means that the insulin is released quickly into your bloodstream, and you should administer it before eating a meal. Because they both contain insulin aspart, the side effects of Fiasp and Novolog are similar. One difference is that Fiasp works faster than Novolog, which means that side effects may occur sooner with Fiasp.

If you have any questions about how the side effects of Fiasp and Novolog compare, talk with your doctor.

Do side effects of Fiasp go away?

Yes, the side effects of Fiasp will go away. Since Fiasp is a rapid-acting insulin, the risk of side effects is greatest in the first 2 hours after using the drug. However, any side effects should disappear once Fiasp has cleared from your body, typically around 6 hours after you take your dose.

Talk with your doctor or pharmacist if you have any questions about how long the side effects of Fiasp may last.

Learn more about some of the side effects that Fiasp may cause. To find out how often side effects occurred in clinical trials, see the prescribing information for Fiasp.

Hypoglycemia

Hypoglycemia (low blood sugar level) is the most common side effect of all insulins, including Fiasp. It was a side effect commonly reported by people using Fiasp in clinical trials. Hypoglycemia can happen suddenly and can be life threatening if it’s not treated quickly. Symptoms of hypoglycemia can include:

  • sweating
  • dizziness
  • confusion
  • hunger

Some people may not be able to recognize the symptoms of low blood sugar easily. This includes people who have had diabetes for a long time, have frequent hypoglycemia, people with diabetic neuropathy, or people taking certain medications such as beta-blockers.

What you can do

Your doctor can advise you on how often to test your blood sugar levels. Regular monitoring of your blood sugar levels can help prevent hypoglycemia.

It’s also important that you and your loved ones know the symptoms of low blood sugar levels and how to treat them. You may want to carry some form of sugar while using Fiasp, such as glucose tablets or sugar cubes. You can use these to raise your blood sugar if it gets too low.

If you have frequent episodes of low blood sugar, talk with your doctor. They may recommend adjusting your insulin dose.

Injection site reactions

Fiasp, like other injectable drugs, can cause a reaction where the drug is injected or infused with an infusion pump. This was a commonly reported side effect in clinical studies of the drug. Injection site reactions were reported more often in people using an insulin pump. Symptoms of injection site reactions can include:

  • pain
  • bruising
  • skin rash
  • swelling
  • redness or discoloration

What you can do

You should rotate the injection or infusion site each time you use Fiasp to help prevent this side effect.

Typically, injection site reactions were mild and went away on their own within a few days. Applying an ice pack to the area may help relieve pain or swelling if your symptoms bother you. Talk with your doctor if your symptoms aren’t going away or are getting worse.

Allergic reaction

As with most drugs, Fiasp can cause an allergic reaction in some people.

Symptoms can be mild or serious and can include:

  • skin rash
  • itching
  • flushing
  • 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 you can do

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

Below is important information you should consider before taking Fiasp.

Other precautions

Before taking Fiasp, discuss your health history with your doctor. Fiasp may not be right for you if you have certain medical conditions or other factors affecting your health. Be sure to talk with your doctor if any of the following apply to you:

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.