- What is insulin, and how does it work (mechanism of action)?
- What brand names are available for insulin?
- Do I need a prescription for insulin?
- What are the uses for insulin?
- What are the side effects of insulin?
- What is the dosage for insulin?
- Is insulin safe to take if I'm pregnant or breastfeeding?
- What else should I know about insulin?
What is insulin, and how does it work (mechanism of action)?
- Insulin is a naturally-occurring hormone secreted by the pancreas. Insulin is required by the cells of the body in order for them to remove and use glucose from the blood. Cells use glucose to produce energy that they need to carry out their functions. Researchers first gave an active extract of the pancreas containing insulin to a young diabetic patient in 1922, and the FDA first approved insulin in 1939. Currently, insulin used for treatment is derived from beef and pork pancreas as well as recombinant (man-made) technology. The first recombinant human insulin was approved by the FDA in 1982.
- People with diabetes mellitus have a reduced ability to take up and use glucose from the blood, and, as a result, the glucose level in the blood rises. In type 1 diabetes, the pancreas cannot produce enough insulin. Therefore, insulin therapy is needed. In type 2 diabetes, patients produce insulin, but cells throughout the body do not respond normally to the insulin. Nevertheless, insulin also may be used in type 2 diabetes to overcome the resistance of the cells to insulin. By increasing the uptake of glucose by cells and reducing the concentration of glucose in the blood, insulin prevents or reduces the long-term complications of diabetes, including damage to the blood vessels, eyes, kidneys, and nerves. Insulin is administered by injection under the skin (subcutaneously). The subcutaneous tissue of the abdomen is preferred because absorption of the insulin is more consistent from this location than subcutaneous tissues in other locations.
What brand names are available for insulin?
Do I need a prescription for insulin?
Yes; No (regular and NPH insulin)
What are the uses for insulin?
What are the side effects of insulin?
- Heart palpitations
- Numbness around the mouth
- Tingling in the fingers
- Muscle weakness
- Blurred vision
- Cold temperature
- Excessive yawning
- Loss of consciousness
Patients may experience blurred vision if they have had elevated blood sugar levels for a prolonged period of time and then have the elevated levels rapidly brought to normal. This is due to a shift of fluid within the lens of the eye. Over time, vision returns to normal. Other side effects that may occur include headaches, skin reactions (redness, swelling, itching or rash at the site of injection), worsening of diabetic retinopathy, changes in the distribution of body fat (lipodystrophy), allergic reactions, sodium retention, and general body swelling. Insulin causes weight gain and may reduce potassium blood levels. In addition to these side effects, inhaled insulin (Afrezza) may cause throat pain or irritation and cough and patients should inform their healthcare professional of any unresolved symptoms affecting the lungs for follow up.
Quick GuideType 2 Diabetes Diagnosis, Treatment, Medication
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