Skip to Content

Insulin aspart / insulin aspart protamine Side Effects

In Summary

Commonly reported side effects of insulin aspart/insulin aspart protamine include: hypoglycemia. Other side effects include: weight gain. See below for a comprehensive list of adverse effects.

For the Consumer

Applies to insulin aspart / insulin aspart protamine: subcutaneous suspension

In addition to its needed effects, some unwanted effects may be caused by insulin aspart / insulin aspart protamine. In the event that any of these side effects do occur, they may require medical attention.

Major Side Effects

You should check with your doctor immediately if any of these side effects occur when taking insulin aspart / insulin aspart protamine:

Incidence not known:
  • Anxiety
  • chills
  • cold sweats
  • confusion
  • dizziness
  • fast heartbeat
  • flushing or redness of the skin
  • headache
  • increased hunger
  • irregular heartbeat
  • itching
  • muscle pain or cramps
  • nausea
  • shakiness
  • skin rash
  • slurred speech
  • sweating
  • swelling

Minor Side Effects

Some of the side effects that can occur with insulin aspart / insulin aspart protamine may not need medical attention. As your body adjusts to the medicine during treatment these side effects may go away. Your health care professional may also be able to tell you about ways to reduce or prevent some of these side effects. If any of the following side effects continue, are bothersome or if you have any questions about them, check with your health care professional:

Incidence not known:
  • Bleeding, blistering, burning, coldness, discoloration of the skin, feeling of pressure, hives, infection, inflammation, itching, lumps, numbness, pain, rash, redness, scarring, soreness, stinging, swelling, tenderness, tingling, ulceration, or warmth at the injection site
  • redistribution or accumulation of body fat

For Healthcare Professionals

Applies to insulin aspart / insulin aspart protamine: subcutaneous suspension


The most common adverse reactions observed with insulin therapy include hypoglycemia, allergic reactions, local injection site reactions, lipodystrophy, rash, and pruritus.[Ref]


Hypoglycemia is the most frequently reported adverse reaction with insulin therapy. It occurs if the dose of the insulin is too high in relation to the insulin requirement. In clinical trials, the frequency of hypoglycemia varied with patient population, dose regimens, and level of glycemic control. Weight gain has been attributed to the anabolic effects of insulin and the decrease in glycosuria.[Ref]

Very common (10% or more): Hypoglycemia (69%)
Frequency not reported: Weight gain[Ref]


Very rare (less than 0.01%): Anaphylactic reactions
Frequency not reported: Allergic reactions[Ref]


Frequency not reported: Injection site reactions[Ref]

Injection site reactions including pain, redness, hives, inflammation, bruising, swelling, and itching, may occur. These reactions are usually transitory.[Ref]


Frequency not reported: Transient, reversible ophthalmologic refraction disorder, worsening of diabetic retinopathy[Ref]

Rapid improvement or intensification of in glucose control has been associated with transitory, reversible ophthalmologic refraction disorder; however, long-term glycemic control decreases the risk of diabetic retinopathy.[Ref]


Insulin may cause sodium retention and edema, especially if previously poor metabolic control is improved by intensified insulin therapy.[Ref]

Frequency not reported: Peripheral edema[Ref]


Frequency not reported: Lipodystrophy, rash, pruritus[Ref]


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


Common (1% to 10%): Influenza-like symptoms
Frequency not reported: Anti-insulin antibodies[Ref]

In a 3-month, open-label study, anti-insulin antibodies and cross-reacting anti-insulin antibodies were monitored in patients using this insulin compared with an insulin mix of 70% NPH (human insulin isophane suspension) and 30% regular (human insulin injection). Changes in cross-reactive antibodies were more common after this mix but these changes did not correlate with a change in HbA1c or increase in insulin dose. The clinical significance of these antibodies has not been established. Antibodies did not increase further after long-term exposure (greater than 6 months).[Ref]


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

Nervous system

Rapid improvement or intensification of in glucose control has been associated with acute and painful peripheral neuropathy; however, long-term glycemic control decreases the risk of neuropathy.[Ref]

Very common (10% or more): Headache (19%)
Common (1% to 10%): Neuropathy[Ref]


Postmarketing reports: Medication errors in which other insulins have been accidentally substituted[Ref]


Common (1% to 10%): Pharyngitis, rhinitis , upper respiratory tract infection[Ref]


1. "Product Information. NovoLog Mix 70/30 FlexPen (insulin aspart-insulin aspart protamine)." Novo Nordisk Pharmaceuticals Inc, Princeton, NJ.

2. Cerner Multum, Inc. "UK Summary of Product Characteristics." O 0

3. Cerner Multum, Inc. "Australian Product Information." O 0

4. "Product Information. NovoLog Mix 70/30 (insulin aspart-insulin aspart protamine)." Novo Nordisk Pharmaceuticals Inc, Princeton, NJ.

Not all side effects for insulin aspart / insulin aspart protamine may be reported. You should always consult a doctor or healthcare professional for medical advice. Side effects can be reported to the FDA here.

Disclaimer: Every effort has been made to ensure that the information provided is accurate, up-to-date and complete, but no guarantee is made to that effect. In addition, the drug information contained herein may be time sensitive and should not be utilized as a reference resource beyond the date hereof. This material does not endorse drugs, diagnose patients, or recommend therapy. This information is a reference resource designed as supplement to, and not a substitute for, the expertise, skill , knowledge, and judgement of healthcare practitioners in patient care. The absence of a warning for a given drug or combination thereof in no way should be construed to indicate safety, effectiveness, or appropriateness for any given patient. does not assume any responsibility for any aspect of healthcare administered with the aid of materials provided. The information contained herein is not intended to cover all possible uses, directions, precautions, warnings, drug interactions, allergic reactions, or adverse effects. If you have questions about the substances you are taking, check with your doctor, nurse, or pharmacist.