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Insulin regular Side Effects

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

For the Consumer

Applies to insulin regular: injection solution

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

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

Incidence not known
  • Anxiety
  • blurred vision
  • chills
  • cold sweats
  • coma
  • confusion
  • convulsions
  • cool, pale skin
  • cough
  • decreased urine
  • depression
  • difficulty swallowing
  • dizziness
  • dry mouth
  • fast heartbeat
  • flushing or redness of the skin
  • headache
  • hives
  • increased hunger
  • increased thirst
  • irregular heartbeat
  • itching
  • loss of appetite
  • muscle pain or cramps
  • nausea
  • nightmares
  • numbness or tingling in the hands, feet, or lips
  • puffiness or swelling of the eyelids or around the eyes, face, lips, or tongue
  • seizures
  • shakiness
  • shortness of breath
  • skin rash
  • slurred speech
  • sweating
  • swelling
  • tightness in the chest
  • unusual tiredness or weakness
  • unusually warm skin
  • wheezing

Some of the side effects that can occur with insulin regular 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 regular: injectable solution, subcutaneous solution


Frequency not reported: Transitory, reversible ophthalmologic refraction disorder, worsening diabetic neuropathy[Ref]

Transitory, reversible ophthalmologic refraction disorder and worsening of diabetic retinopathy has been reported with insulin initiation and glucose control intensification. Over the long-term, improved glycemic control decreases the risk for diabetic neuropathy.[Ref]


Uncommon (0.1% to 1%): Lipodystrophy[Ref]

Long-term use of insulin can cause lipodystrophy at the site of repeated insulin injections. Lipodystrophy includes lipohypertrophy (thickening of adipose tissue) and lipoatrophy (thinning of adipose tissues).[Ref]


Uncommon (0.1% to 1%): Local reactions such as redness, swelling, or itching at the injection site
Very rare (less than 0.01%): Anaphylactic reactions[Ref]

Hypersensitivity reactions 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. In some instances these reactions have been caused by other factors such as irritants in a skin cleansing agent or poor injection technique. Localized reactions have been reported with metacresol, which is an excipient in many insulin products.

Generalized allergy to insulin may present as a whole body rash, dyspnea, wheezing, hypotension, tachycardia, or diaphoresis.[Ref]


Increases in titers of anti-insulin antibodies that react with human insulin have been observed; some data indicates the increase is transient. The clinical significance of these antibodies is unknown; it does not appear to cause deterioration in glycemic control.[Ref]

Frequency not reported: Formation of anti-insulin antibodies[Ref]


Frequency not reported: Sodium retention and edema[Ref]

Insulin may cause sodium retention and edema, especially with intensified insulin therapy. Combination use with thiazolidinediones has resulted in fluid retention which has led to or exacerbated heart failure.[Ref]


Adverse reactions reported with this insulin include hypoglycemia, allergic reactions, injection site reactions, lipodystrophy, weight gain, and edema[Ref]


Very common (10% or more): Hypoglycemia
Rare (less than 0.1%): Insulin resistance
Frequency not reported: Hypokalemia, hyperglycemia, diabetic ketoacidosis, hyperosmolar hyperglycemic non-ketotic syndrome, hypomagnesemia, hypophosphatemia[Ref]

Hypoglycemia is the most common adverse reaction of all insulin therapies. The timing of hypoglycemia generally reflects the time-action profile of the administered insulin, however, the time action profile of any insulin may vary considerably in different individuals or at different times in the same individual depending on dose, site of injection, blood supply, temperature, and physical activity. Other factors such as changes in food intake (timing of meals, amount or type of food) and concomitant medications will also affect the risk of hypoglycemia.

Hypokalemia, which is due to a shift in potassium from the extracellular to the intracellular space, occurs with all insulins. Hypokalemia and hypomagnesemia has been reported, particularly in patients treated for diabetic ketoacidosis (DKA). Insulin increases the intracellular transport of phosphate, which often results in hypophosphatemia during treatment of DKA. In situations in which not enough insulin is available to control blood glucose, hyperglycemia, diabetic ketoacidosis, and hyperosmolar hyperglycemic non-ketotic syndrome may occur.[Ref]


Injection site reactions including pain, redness, hives, inflammation, bruising, swelling, and itching have occurred. These usually resolve in a few days to a few weeks; rotation of the injection site reduces the risk of these reactions developing.[Ref]

Common (1% to 10%): Injection site hypertrophy
Frequency not reported: Injection site reactions[Ref]

Nervous system

Frequency not reported: Acute painful peripheral neuropathy[Ref]

Acute painful peripheral neuropathy has been reported with insulin initiation and glucose control intensification. Over the long-term, improved glycemic control decreases the risk for neuropathy.[Ref]


Weight gain can occur with insulin use; it is believed to be due to the anabolic effects of insulin and the decrease in glucosuria.[Ref]

Frequency not reported: Weight gain[Ref]


1. "Product Information. NovoLIN R (insulin regular)." 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. Humulin R (insulin regular)." Lilly, Eli and Company, Indianapolis, IN.

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