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Fiasp Side Effects

Generic name: insulin aspart

Medically reviewed by Last updated on Mar 4, 2024.

Note: This document contains side effect information about insulin aspart. Some dosage forms listed on this page may not apply to the brand name Fiasp.

Applies to insulin aspart: solution.

Serious side effects of Fiasp

Along with its needed effects, insulin aspart (the active ingredient contained in Fiasp) may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.

Check with your doctor immediately if any of the following side effects occur while taking insulin aspart:

More common

Less common


Other side effects of Fiasp

Some side effects of insulin aspart may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. Also, your health care professional may be able to tell you about ways to prevent or reduce some of these side effects.

Check with your health care professional if any of the following side effects continue or are bothersome or if you have any questions about them:

More common

For Healthcare Professionals

Applies to insulin aspart: injectable solution, subcutaneous solution.


Adverse reactions observed have included hypoglycemia, allergic reactions, local injection site reactions, lipodystrophy, rash, and pruritus.[Ref]


Very rare (less than 0.01%): Anaphylaxis

Common (1% to 10%): Allergic skin manifestations

Frequency not reported: Allergic reactions[Ref]

Hypersensitivity side effects have included both local and systemic reactions. Anaphylaxis has been reported. Local reactions have presented as erythema, local edema, and pruritus at the injection site. Most minor reactions to insulin at the injection site resolve in a few days to a few weeks.

Generalized allergy to insulin may present as a whole body rash, dyspnea, wheezing, hypotension, tachycardia, or diaphoresis. In clinical trials, allergic reactions were reported in 0.7% (10/1394) patients receiving insulin aspart.

Clinical trials with Fiasp(R) reported generalized hypersensitivity reactions at 0.2% (comparator 0.1%). Anaphylactic reactions were not reported. Allergic skin manifestations were reported at 1.5% (comparator 1.4%) and included eczema, rash, pruritic rash, urticaria, and dermatitis.[Ref]


Weight gain has been reported with insulin therapy and has been attributed to the anabolic effects of insulin and the decrease in glucosuria.[Ref]

Very common (10% or more): Hypoglycemia

Frequency not reported: Weight gain[Ref]


Localized cutaneous amyloidosis at the injection site has been reported with resultant hyperglycemia with repeated insulin injections into that area; hypoglycemia has been reported with a sudden change to an unaffected injection site.

Common (1% to 10%): Injection site reactions (including rash, redness, inflammation, pain, itching, and bruising)

Frequency not reported: Lipodystrophy (including lipohypertrophy, lipoatrophy)

Postmarketing reports: Localized cutaneous amyloidosis at injection site


Insulin may cause sodium retention and edema, especially as metabolic control is improving.[Ref]

Common (1% to 10%): Chest pain

Uncommon (0.1% to 1%): Peripheral edema[Ref]


Common (1% to 10%): Skin disorder, eczema, dermatitis

Uncommon (0.1% to 1%): Urticaria, rash

Frequency not reported: Lipodystrophy including lipohypertrophy and lipoatrophy[Ref]

Long-term use of insulin may cause lipodystrophy at the site of repeated injection. Lipodystrophy includes lipohypertrophy, a thickening of adipose tissue, and lipoatrophy, thinning of adipose tissue.[Ref]


Common (1% to 10%): Onychomycosis

Frequency not reported: Anti-insulin antibody titers[Ref]

The clinical significance of the development of these antibody titers is unknown.[Ref]


Uncommon (0.1% to 1%): Refraction disorder, worsening of diabetic retinopathy[Ref]

Rapid improvement in glucose control has been associated with a transitory, reversible ophthalmologic refraction disorder and worsening of diabetic retinopathy. However, long-term glycemic control decreases the risk of diabetic retinopathy.[Ref]

Nervous system

Very common (10% or more): Headache (up to 12%)

Common (1% to 10%): Hyporeflexia, sensory disturbance

Rare (less than 0.1%): Painful peripheral neuropathy[Ref]

Rapid improvement in glucose control has been associated with a transitory, reversible acute painful peripheral neuropathy. However, long-term glycemic control decreases the risk.[Ref]


Common (1% to 10%): Nausea, diarrhea, abdominal pain[Ref]


Common (1% to 10%): Urinary tract infection[Ref]


Common (1% to 10%): Back pain[Ref]


Very common (10% or more): Nasopharyngitis (23%)

Common (1% to 10%): Upper respiratory infection[Ref]

Frequently asked questions


1. (2022) "Product Information. NovoLOG (insulin aspart)." Novo Nordisk Pharmaceuticals Inc

2. Cerner Multum, Inc. "UK Summary of Product Characteristics."

3. Cerner Multum, Inc. "Australian Product Information."

4. (2017) "Product Information. Fiasp (insulin aspart)." Novo Nordisk Pharmaceuticals Inc

Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.

Some side effects may not be reported. You may report them to the FDA.