Insulin: Types, Mechanism, Uses, and Adverse Effects

• Rapid-acting Insulin: Examples include insulin lispro, insulin aspart, insulin glulisine. Onset: 10–30 minutes, Peak: 30 minutes to 3 hours, Duration: 3–5 hours.
• Short-acting Insulin (Regular Insulin): Examples include regular insulin (Humulin R, Novolin R). Onset: 30–60 minutes, Peak: 2–5 hours, Duration: 5–8 hours.
• Intermediate-acting Insulin: Examples include NPH insulin (Humulin N, Novolin N). Onset: 1–2 hours, Peak: 4–12 hours, Duration: 12–18 hours.
• Long-acting Insulin: Examples include insulin glargine (Lantus), insulin detemir (Levemir). Onset: 1–2 hours, Peak: No pronounced peak, Duration: Up to 24 hours.
• Ultra-long-acting Insulin: Examples include insulin degludec (Tresiba). Onset: 30–90 minutes, Peak: No peak, Duration: 36–42 hours.

Note: Inhaled Insulin

• Examples: Afrezza
• Onset: 12–15 minutes
• Peak: 30–60 minutes
• Duration: 2–3 hours
• Information: Inhaled insulin is a rapid-acting form administered via the lungs. It is used to control post-meal blood sugar spikes. Not recommended for individuals with lung disease, as it may cause respiratory side effects and requires lung function monitoring.

Insulin facilitates the uptake of glucose into muscle and adipose cells via insulin receptors. It stimulates glycogenesis (the formation of glycogen from glucose), inhibits gluconeogenesis (production of glucose from non-carbohydrate sources), and enhances fat storage, lowering blood glucose levels and supporting energy metabolism.

• Type 1 Diabetes Mellitus: Essential for managing blood glucose levels in patients with little or no insulin production.
• Type 2 Diabetes Mellitus: Used when oral medications fail to control blood glucose levels.
• Gestational Diabetes: Administered during pregnancy when blood glucose levels cannot be managed through diet and exercise alone.
• Diabetic Ketoacidosis (DKA): Used in emergency situations to prevent diabetic coma and regulate blood glucose levels.

• Hypoglycemia: Common and serious, causing symptoms such as sweating, trembling, and confusion.
• Weight Gain: Insulin promotes fat storage, often leading to weight gain.
• Injection Site Reactions: Can cause redness, swelling, or lipohypertrophy.
• Allergic Reactions: Rare, but can include rashes or anaphylaxis.
• Insulin Resistance: Long-term use may lead to insulin resistance, requiring higher doses.