What is the blood glucose lowering effect of one unit of insulin Lispro (Humalog)?

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From the FDA Drug Label

One unit of HUMALOG has the same glucose-lowering effect as one unit of regular human insulin.

The amount by which one unit of Lispro drops blood sugar is not explicitly quantified in the provided drug label. However, it is stated that one unit of HUMALOG has the same glucose-lowering effect as one unit of regular human insulin 1.

  • The glucose-lowering effect of one unit of insulin is not specified.
  • The label provides information on the pharmacodynamics and pharmacokinetics of HUMALOG, but does not provide a direct answer to the question of how much one unit of Lispro drops blood sugar.

From the Research

Lispro insulin typically lowers blood sugar by approximately 1.5-2 mg/dL per unit for most adults, though this effect varies significantly between individuals. This rapid-acting insulin begins working within 15-30 minutes, peaks in 30-90 minutes, and lasts about 3-5 hours total. The blood glucose-lowering effect depends on several factors including the person's insulin sensitivity, body weight, activity level, concurrent medications, and overall metabolic state. Someone who is insulin resistant may see less effect per unit, while those who are more insulin sensitive might experience a greater drop. Healthcare providers often use a starting estimate of 1 unit lowering blood sugar by about 50 mg/dL for correction doses, but this must be individualized through careful monitoring and adjustment, as noted in various studies on diabetes management 2, 3, 4, 5, 6.

Key Factors Influencing Insulin Effect

  • Insulin sensitivity
  • Body weight
  • Activity level
  • Concurrent medications
  • Overall metabolic state

It's essential to work with a healthcare provider to determine your personal insulin sensitivity factor, as using too much insulin can cause dangerous hypoglycemia. The management of diabetes and the use of insulins like Lispro must consider the complex interplay of factors influencing glucose metabolism, including the role of glucagon 5 and the potential for hypoglycemic episodes 3, 4.

Considerations for Clinical Practice

  • Individualize insulin dosing based on patient factors
  • Monitor blood glucose levels closely
  • Adjust insulin doses as needed to prevent hypoglycemia
  • Educate patients on the signs and symptoms of hypoglycemia and how to manage it effectively.

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Professional Medical Disclaimer

This information is intended for healthcare professionals. Any medical decision-making should rely on clinical judgment and independently verified information. The content provided herein does not replace professional discretion and should be considered supplementary to established clinical guidelines. Healthcare providers should verify all information against primary literature and current practice standards before application in patient care. Dr.Oracle assumes no liability for clinical decisions based on this content.

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