Why do I need an insulin in blood test?

You may need an insulin in blood test if you:

• Had a blood glucose test that showed you have low blood glucose levels.
• Have symptoms of hypoglycemia (low blood glucose). Symptoms of mild to moderate hypoglycemia include:
  • Sweating
  • Feeling shaky or jittery
  • Arrythmia (a problem with the rate or rhythm of your heartbeat)
  • Confusion
  • Dizziness
  • Headache
  • Hunger

  Severe hypoglycemia can cause fainting and seizures. This serious condition needs medical treatment right way.

• Have insulin resistance or have a high risk for developing it. Your risk for insulin resistance is higher if you have:
  • Prediabetes
  • Type 2 diabetes
  • Polycystic ovary syndrome (PCOS)
  • Heart disease
  • Acanthosis nigricans (dark, thick, velvety skin around the neck or armpits)
• Had surgery on your pancreas:
  • To transplant the part of the pancreas that makes insulin (islet cell transplantation). You may need insulin testing to see if the transplant is working properly.
  • To remove an insulinoma. This is a tumor in the pancreas that makes too much insulin and causes low blood glucose. After surgery you may need insulin testing to check whether any tumor tissue is left and to see if the tumor has come back. Insulinomas are uncommon and usually aren't cancer.