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Drugs, Supplies and Delivery
Insulin Lispro (Humalog® Injection)
Insulin lispro, marketed as Humalog®, is a rapid-acting insulin analog used to manage hyperglycemia in type 1 and type 2 diabetes mellitus. Engineered for rapid onset and short duration, it closely mimics physiological insulin secretion, making it ideal for mealtime glucose control. This article synthesizes evidence from the British National Formulary (BNF), Lippincott Textbook of Pharmacology, and Lange Basic & Clinical Pharmacology to detail its pharmacology, clinical use, and safety profile
Insulin lispro is structurally modified (lysine and proline residues swapped at positions B28 and B29) to accelerate absorption and action. Key mechanisms include: Glucose Uptake: Binds to insulin receptors, promoting cellular glucose absorption via GLUT4 transporters in muscle and adipose tissue.
Hepatic Glucose Suppression: Inhibits glycogenolysis and gluconeogenesis. Peripheral Utilization: Enhances glycogen synthesis and protein/lipid metabolism |
Onset: 15–30 minutes (subcutaneous).
Peak: 0.5–2.5 hours.
Duration: 3–5 hours (Lippincott).
Intravenous Use: Reserved for emergencies (e.g., diabetic ketoacidosis [DKA]) under clinical supervision (BNF).
Type 1 Diabetes:
Mealtime insulin in basal-bolus regimens, paired with long-acting insulin.
Compatible with continuous subcutaneous insulin infusion (CSII) via insulin pumps.
Type 2 Diabetes:
Adjunctive therapy when oral agents or non-insulin injectables fail to achieve glycemic targets
Administration:
Subcutaneous: Inject into abdomen, thigh, or upper arm 0–15 minutes before meals.
IV: Diluted in infusion systems for critical care (0.05–0.1 units/kg/h).
Initial Dosing:
Adults: 0.2–0.4 units/kg/day, divided into pre-meal doses.
Children: 0.5–1.0 units/kg/day, adjusted by carbohydrate intake and activity (BNF).
Titration: Adjust weekly based on pre- and postprandial glucose monitoring.
Special Populations:
Renal/Hepatic Impairment: Monitor closely; hypoglycemia risk increases with reduced insulin clearance.
Elderly: Conservative dosing to avoid hypoglycemia (Lange).
Hypoglycemia: Symptoms include tremors, sweating, confusion.
Injection-Site Reactions: Redness, itching, or lipodystrophy with chronic use.
Weight Gain: Due to anabolic effects.
Serious:
Severe Hypoglycemia: Risk with overdose, missed meals, or exercise.
Hypokalemia: Insulin shifts potassium intracellularly; monitor in critical care.
Allergic Reactions: Rare urticaria or anaphylaxis (BNF).
Contraindications: Hypoglycemia, hypersensitivity to insulin lispro
Blood glucose (pre-/postprandial and bedtime).
HbA1c (every 3–6 months), renal/hepatic function.
Injection sites for lipodystrophy; rotate sites regularly
Unopened vials/pens: Refrigerate (2–8°C).
In-use: Store at room temperature (<30°C) for up to 28 days
Pregnancy: Category B; safe with dose adjustments as needed.
Lactation: Safe; insulin does not enter breast milk (Lippincott
Beta-Blockers: Mask hypoglycemia symptoms (e.g., tachycardia).
Corticosteroids/Thiazides: Increase insulin resistance, requiring dose escalation.
ACE Inhibitors: Enhance insulin sensitivity, raising hypoglycemia risk.
Alcohol: Potentiates hypoglycemia; avoid concurrent use (BNF).
Generic: Insulin lispro.
Brand Names: Humalog® (Eli Lilly), other regional variants (e.g., Liprolog® in the EU).
