The most effective treatment was to put patients with diabetes on very stict diets with minimal carbohydrate intake. This could buy patients a few extra years but couldn’t save them. Harsh diets sometimes even caused patients to die of starvation. In 1922 Leonard Thompsons, a 14 year old boy dying of diabetes in Toronto hospital, became the first person to receive an injection of insulin. Within 24 hours Leonard’s dangerously high blood glucose levels dropped to near normal levels. In 1923 Banting and Macleod were awarded the Nobel Prize in physiology and medicine for the discovery of insulin.
Initially insulin was available in bovine or porcine preparations. In 1980`s, recombinant human insulin was introduced. Insulin analogues with better pharmacokinetic profiles were introduced in 1990`s to provide greater flexibility to patients on insulin therapy.
Insulin should be given to all patients with type 1 diabetes, which is due to auto immune islet cell injury that eventually leads to virtual complete insulin deficiency . Any new onsite diabetes mellitus with high blood gloucose levels should be treated with insulin therapy. Insulin is indicated for patients with secondary diabetes due to pancreatic insufficiency, as well as in many patients with type 2 diabetes to manage hyperglycemia. It is also indicated in patents with renal failure, stroke, and coronary artery disease. Insulin is the only drug approved for use in gestational diabetes.
1) Short acting insulin: Regular
Regular insulin, because of its slow rate of absorption it has an onset of action 15 to 60 minutes after injection, peak effect 2 to 4 hrs and duration of action ranging 5 to 8 hours.
2) Intermediate acting insulin: NPH
They are modified into a suspension foam to delay thin absorption. Onset of action is within 2 to 3 hr of injection, with peak action 5 to 7 hrs and duration of action ranging from 13 to 16 hours. Its effective In controlling fasting and pre dinner glucose levels.
1) Rapid acting insulin: Lispro and Aspart starts acting within 15 minutes, reaches peak in 60 to 90 minutes and acts up to 4 to 5 hours. They are used as a meal time insulin. They provide more flexibility to the patients because they need not be administered 30 minutes prior to meal and the dose can be readily adjusted according to carbohydrate content of the meal.
2) Long acting insulin analogues: Calargine it has prolonged duration of action. It has no pronounced insulin peak, decreasing the risk of nocturnal hypoglycemia.
Premixed preparation of short and intermediate acting insulin is available. Commonly used preparations are 30/70 and 50/50 which contains 30% short acting with 70% intermediate acting insulin, 50 % short acting and 50% intermediate acting insulin respectively. Analogue insulin are also available in 25/25 and 50/50 preparations. Such preparations are often convenient for the patient in reducing the number of needle pricks.
1) Syringe and needle
2) Pen devices- convenient, easy to carry and less discomfort due to fine needle.
3) Insulin pump – continuous insulin injection.
1 storage: stable at room temperature (less than 35) for 30 days. Vials not in use to be stored in refrigerator.
2 insulin technique: injected into the subcutaneous tissue with the skin gently pinched between thumb and forefinger and injected at a perpendicular angle. Massage of the local area can increase the rate of absorption, as can increased skin temperature.
3 blood glucose monitoring: frequency of monitoring depends on the type of insulin regime.
- Weight gain
- Lipohypertrophy/ lipoartophy
- Insulin allergy
Insulin now comes in many forms, from regular human insulin identical to what the body produces to ultra rapid and ultra long acting insulin. Thanks to decades to research, people with diabetes can choose from a variety of formulas and ways to take their insulin based on their personal needs and lifestyles. From humalog to novolog and insulin pens to pumps, insulin has come a long way.