Diabetes is a chronic health condition that affects how the body converts food into energy. When a person has diabetes, their body either does not produce enough insulin or cannot effectively use the insulin it does produce, leading to elevated blood glucose levels. For many individuals managing this condition, injectable medications are an important part of maintaining healthy blood glucose levels. These specialized treatments are prescribed and guided by healthcare professionals for safe and effective management.
Insulin Therapy
Insulin is a hormone naturally produced by the pancreas, acting as a “key” that allows glucose from the bloodstream to enter cells for energy. In individuals with type 1 diabetes, the pancreas produces little to no insulin, necessitating external insulin administration to survive. People with type 2 diabetes may initially produce insulin but either not enough or their bodies do not respond well to it, often requiring insulin injections as the condition progresses.
Since insulin is a protein, it would be broken down and rendered ineffective by the digestive system if taken orally, which is why it must be injected. Various types of insulin are available, categorized by how quickly they start working, when they peak, and how long their effects last. Each type mimics the body’s natural insulin release patterns.
Rapid-acting insulins, such as insulin lispro, insulin aspart, and insulin glulisine, begin working within 5 to 15 minutes, peak in about 30 to 90 minutes, and last for 3 to 5 hours. These are usually taken just before or with meals to cover carbohydrate intake. Short-acting, or regular, insulins like Humulin R or Novolin R, start acting within 30 to 60 minutes, peak in 2 to 4 hours, and last for 5 to 8 hours. They are administered about 30 minutes before a meal.
Intermediate-acting insulins, such as NPH (Neutral Protamine Hagedorn), begin to lower blood sugar in 1 to 3 hours, peak in 6 to 10 hours, and last for 10 to 16 hours. These insulins provide background coverage for about half a day, taken once or twice daily. Long-acting insulins, including insulin glargine and insulin detemir, provide a steady, peakless supply of insulin for up to 24 hours. They are taken once or twice daily to provide constant basal insulin coverage. Pre-mixed insulins combine two types of insulin, often a rapid or short-acting insulin with an intermediate-acting insulin, offering convenience by covering both mealtime and basal needs with fewer injections.
Other Injectable Diabetes Medications
Beyond insulin, other injectable medications are used in diabetes management. These medications work through different mechanisms than insulin and can be used alone or in combination with insulin or oral medications. One class of these injectables includes GLP-1 receptor agonists.
GLP-1 receptor agonists, such as liraglutide, semaglutide, dulaglutide, and tirzepatide, are not insulin but work by mimicking natural hormones called incretins. When blood sugar levels are high, these medications stimulate the pancreas to release more insulin. They also slow down stomach emptying, which helps reduce post-meal blood sugar spikes, and decrease glucagon released by the pancreas, a hormone that raises blood sugar. Many individuals also experience reduced appetite and weight loss.
Amylin analogs are another type of injectable medication, with pramlintide as an example. Amylin is a hormone co-secreted with insulin from the pancreas. Pramlintide is used in conjunction with insulin for both type 1 and type 2 diabetes. It slows food movement from the stomach, reduces post-meal glucagon secretion, and promotes fullness. These actions improve blood glucose control, especially after meals.
Safe Injection Practices
Proper injection technique is important for the effectiveness of diabetes medications and to prevent complications. Choosing and rotating injection sites helps to prevent lipohypertrophy, lumps of fat that affect medication absorption. Common injection sites include the abdomen, thighs, upper arms, and buttocks, with the abdomen preferred due to consistent absorption.
Before each injection, wash hands thoroughly with soap and water. The medication should be checked for clarity, absence of particles, and its expiration date. The injection device, whether a pen or syringe, should be prepared according to its specific instructions, involving attaching a new needle and performing an air shot to remove any air bubbles.
The chosen injection site should be cleaned with an alcohol swab and allowed to air dry completely before injection. Gently pinching the skin at the site helps ensure the medication is delivered into the subcutaneous fat layer. Insert the needle at a 90-degree angle, or 45 degrees if the skinfold is small, and inject the medication slowly. After injecting, hold the needle in place for a few seconds before withdrawing to ensure the full dose.
Safe disposal of used needles and syringes prevents accidental needle sticks. All used sharps should be immediately placed into a designated sharps container, a puncture-resistant, leak-proof container. Once full, these containers should be disposed of according to local guidelines. Unopened insulin and other injectable medications require refrigeration, while opened vials or pens can be stored at room temperature for a specified period, typically 28 days, away from direct sunlight or extreme temperatures. Hands-on training from a healthcare provider or diabetes educator is important to learn the correct and safe way to administer specific injectable medications.