What are the side effects of Basaglar (insulin glargine)?

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Side Effects of Basaglar (Insulin Glargine)

The most common side effects of Basaglar (insulin glargine) include hypoglycemia, weight gain, injection site reactions, allergic reactions, and lipodystrophy at the injection site. 1

Common Side Effects

Hypoglycemia

  • Most serious and common side effect
  • Signs and symptoms include:
    • Dizziness or light-headedness
    • Sweating
    • Confusion
    • Headache
    • Blurred vision
    • Slurred speech
    • Shakiness
    • Fast heartbeat
    • Anxiety, irritability, mood changes
    • Hunger

Weight Gain

  • Common side effect of insulin therapy
  • May be managed through diet and exercise

Injection Site Reactions

  • Local reactions at the site of injection:
    • Redness
    • Swelling
    • Itching
    • Pain

Skin Changes

  • Lipodystrophy (pits in skin or thickened skin)
  • Localized cutaneous amyloidosis (skin with lumps)
  • Can be minimized by rotating injection sites

Serious Side Effects

Severe Allergic Reactions

  • Whole body reactions requiring immediate medical attention:
    • Rash over the whole body
    • Trouble breathing
    • Fast heartbeat
    • Sweating

Hypokalemia

  • Low potassium levels in the blood
  • Can lead to cardiac arrhythmias

Heart Failure

  • Risk increases when taking thiazolidinediones (TZDs) with insulin glargine
  • Symptoms include:
    • Shortness of breath
    • Swelling of ankles or feet
    • Sudden weight gain

Special Considerations

Nocturnal Hypoglycemia

  • Insulin glargine has a lower risk of nocturnal hypoglycemia compared to NPH insulin due to its more stable 24-hour glucose-lowering profile 2
  • This is one of the principal advantages of insulin glargine over NPH insulin 3

Overdose Risk

  • Overdose can cause prolonged hypoglycemia (48-96 hours)
  • May require continuous intravenous glucose infusion
  • Can affect electrolytes and potentially cause acute hepatic injury 4

Administration Precautions

  • Do not mix Basaglar with any other insulin or liquid medicine 1
  • Only use insulin that is clear and colorless
  • Do not use in insulin pumps or inject intravenously
  • Rotate injection sites to reduce risk of lipodystrophy
  • Store according to manufacturer recommendations

Drug Interactions

  • Taking TZDs with insulin glargine may increase risk of heart failure 1
  • Alcohol consumption may increase hypoglycemia risk
  • Monitor closely when using with other medications that can affect blood glucose levels

Monitoring Recommendations

  • Regular blood glucose monitoring is essential to detect and prevent hypoglycemia
  • Be especially vigilant during the first four weeks after switching to insulin glargine, as this is when hypoglycemia risk is highest 5
  • Patients should be educated on recognizing and managing hypoglycemic episodes

Understanding these side effects and taking appropriate precautions can help patients safely use Basaglar while minimizing adverse events and optimizing glycemic control.

References

Guideline

Managing Morning Hyperglycemia in Insulin Users

Praxis Medical Insights: Practical Summaries of Clinical Guidelines, 2025

Research

Insulin Glargine: a review 8 years after its introduction.

Expert opinion on pharmacotherapy, 2009

Research

Insulin glargine: a new long-acting insulin product.

American journal of health-system pharmacy : AJHP : official journal of the American Society of Health-System Pharmacists, 2002

Professional Medical Disclaimer

This information is intended for healthcare professionals. Any medical decision-making should rely on clinical judgment and independently verified information. The content provided herein does not replace professional discretion and should be considered supplementary to established clinical guidelines. Healthcare providers should verify all information against primary literature and current practice standards before application in patient care. Dr.Oracle assumes no liability for clinical decisions based on this content.

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