What is Lispro (Humalog, insulin lispro)?

From the Guidelines

Lispro, also known as Humalog, is a rapid-acting insulin analog that plays a crucial role in managing blood glucose levels in people with diabetes, particularly in preventing post-meal blood sugar spikes. It is characterized by its fast onset of action, beginning to work within 15 minutes after injection, peaking in about 1 hour, and continuing to work for 2-4 hours 1. The typical starting doses of Lispro range from 0.1-0.2 units/kg/day, divided before meals, though dosing must be individualized based on blood glucose monitoring 1.

Key Characteristics of Lispro

• Begins working within 15 minutes after injection
• Peaks in about 1 hour
• Continues working for 2-4 hours
• Should be injected subcutaneously in the abdomen, thigh, arm, or buttocks immediately before meals
• Offers greater flexibility in meal planning compared to premixed insulin

Administration and Compatibility

Lispro should be administered subcutaneously in the abdomen, thigh, arm, or buttocks immediately before meals. It is compatible with longer-acting insulins for complete diabetes management and can be used in insulin pumps 1. Patients should rotate injection sites to prevent lipodystrophy and always carry fast-acting glucose to treat low blood sugar.

Side Effects and Considerations

Side effects of Lispro may include hypoglycemia, injection site reactions, and allergic responses. The FDA has approved a concentrated formulation of rapid-acting insulin called lispro U-200, which may be more suitable for some patients because the volume of insulin being injected is significantly less than U-100 insulins, potentially improving adherence for those who require large doses of insulin 1.

Clinical Use

In clinical practice, Lispro is often considered for patients with type 2 diabetes who require insulin therapy, particularly when basal insulin alone does not achieve HbA1c targets. Adding a single injection of rapid-acting insulin analogue like Lispro before the largest meal is a recommended approach for further treatment intensification 1. The choice between Lispro and other rapid-acting insulin analogues, such as aspart or glulisine, may depend on individual patient factors, including cost, insurance coverage, and personal preference.

From the FDA Drug Label

HUMALOG® (insulin lispro injection, USP [rDNA origin]) is a rapid-acting human insulin analog used to lower blood glucose. Insulin lispro is produced by recombinant DNA technology utilizing a non-pathogenic laboratory strain of Escherichia coli Insulin lispro differs from human insulin in that the amino acid proline at position B28 is replaced by lysine and the lysine in position B29 is replaced by proline.

Lispro (Humalog, insulin lispro) is a rapid-acting human insulin analog used to lower blood glucose. It is produced by recombinant DNA technology and differs from human insulin in its amino acid structure, with proline at position B28 replaced by lysine and the lysine in position B29 replaced by proline 2.

From the Research

Definition and Characteristics of Lispro

• Lispro, also known as insulin lispro, is a rapid-acting insulin analog 3.
• It is a new insulin analog with a rapid absorption rate, fast onset, and shorter duration of action compared to regular insulin 3.
• The inversion of the proline-lysine amino acid sequence at positions 28 and 29 on the B chain is responsible for its rapid absorption and faster onset of action 3.

Comparison with Regular Insulin

• Insulin lispro provides equivalent or slightly improved glycemic control in patients with types I and II diabetes mellitus compared to regular insulin 3.
• It results in a greater reduction in postprandial blood glucose excursion than regular insulin 3.
• Insulin lispro has a more rapid onset and shorter duration of action than regular insulin, which may reduce the risk of hypoglycemia 4.

Clinical Applications and Benefits

• Insulin lispro is effective in improving postprandial glucose control 5, 6, 7.
• It allows for greater flexibility in dosing and mealtime scheduling 3.
• Patients using insulin lispro perceive an improvement in their well-being and quality of life due to flexible injection times and less frequent hypoglycemic reactions 4.
• Insulin lispro is believed to be suitable for patients using insulin infusion pumps 4.

Pharmacokinetics and Administration

• Subcutaneous injections of insulin lispro result in decreased blood glucose peaks following meals and a potential decreased risk of hypoglycemic episodes 4.
• The peak serum insulin concentration of insulin lispro is three times higher, time to peak is 4.2 times faster, the absorption rate constant is double, and the duration of action is half as long compared to regular human insulin 4.
• When insulin lispro is mixed with human NPH (isophane) or Lente insulins, insulin lispro should be drawn into the syringe first, mixed with the long-acting insulin, and injected immediately after mixing 4.