Last reviewed 2026-04-23 · How we verify

Humulin L

Humulin L is a long-acting insulin that binds to insulin receptors to facilitate glucose uptake and utilization in peripheral tissues.

Humulin L is a long-acting insulin that binds to insulin receptors to facilitate glucose uptake and utilization in peripheral tissues. Used for Type 1 diabetes mellitus, Type 2 diabetes mellitus.

At a glance

Mechanism of action

Humulin L (insulin zinc suspension) is a basal insulin formulation that provides prolonged glycemic control by mimicking endogenous insulin secretion. It works by binding to insulin receptors on muscle and adipose tissue, promoting glucose uptake and storage while suppressing hepatic glucose production. The zinc suspension formulation extends the duration of action compared to regular insulin.

Approved indications

• Type 1 diabetes mellitus
• Type 2 diabetes mellitus

Common side effects

• Hypoglycemia
• Weight gain
• Injection site reactions
• Lipodystrophy

Key clinical trials

• Impact on Birth Weight of Two Therapeutic Strategies (Insulin Therapy From the Beginning of Pregnancy vs. Insulin Therapy Initiated According to Fetal Growth Evaluated by Ultrasonography Measurements) in Pregnant Women With Monogenic Diabetes (NA)
• Glycemic Control After Antenatal Corticosteroids in Women With Pregestational and Gestational Diabetes (PHASE2)
• Glycemic Targets During CPB in Elderly Diabetes (NA)
• Isoleucine Addition Treatment Effects in a Controlled Diet Study (NA)
• Physical Activity to Prevent and Treat Hyperglycemia From a Mistimed Bolus Insulin Dose (NA)
• Allo HSCT for High Risk Hemoglobinopathies (PHASE2)
• PROCHYMAL® (Human Adult Stem Cells) for the Treatment of Recently Diagnosed Type 1 Diabetes Mellitus (T1DM) (PHASE2)
• Prevention of Mild-to-moderate Hypoglycemia in Type 1 Diabetes (NA)

Primary sources

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