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NovoLog Mix 50 / 50 Side Effects

Generic Name: insulin aspart / insulin aspart protamine

Note: This page contains side effects data for the generic drug insulin aspart / insulin aspart protamine. It is possible that some of the dosage forms included below may not apply to the brand name NovoLog Mix 50 / 50.

For the Consumer

Applies to insulin aspart / insulin aspart protamine: subcutaneous suspension

As well as its needed effects, insulin aspart / insulin aspart protamine may cause unwanted side effects that require medical attention.

Major Side Effects

If any of the following side effects occur while taking insulin aspart / insulin aspart protamine, check with your doctor immediately:

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 insulin aspart / insulin aspart protamine side effects may not need any medical attention. As your body gets used to the medicine these side effects may disappear. Your health care professional may be able to help you prevent or reduce these side effects, but do check with them if any of the following side effects continue, or if you are concerned about them:

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. "Australian Product Information." O 0

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

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

It is possible that some side effects of NovoLog Mix 50 / 50 may not have been reported. These can be reported to the FDA here. Always consult a healthcare professional for medical advice.

More about NovoLog Mix 50/50 (insulin aspart / insulin aspart protamine)

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