Humalog® (insulin lispro): a rapid-acting insulin
Humalog® is the brand name for insulin lispro, a short-acting medicine prescribed to lower blood sugar levels in people with diabetes. The medicine derives its name from being an analog of human insulin. An insulin analog means that its molecular structure is almost identical to the natural insulin hormone produced in the body.
The FDA has approved Humalog to be used by individuals with either type 1 or type 2 diabetes.
How Humalog works
Humalog lowers blood glucose levels by rapidly signaling fat and skeletal tissue to absorb glucose from the blood stream, and also by signaling the liver to stop producing glucose. Once glucose leaves the blood stream, the tissues can use it for energy. Humalog has been shown through clinical studies to be just as potent as normal human insulin, but it acts more quickly and the duration of activity is shorter.
Humalog is produced in the form of a liquid solution that is injected under the skin. It is typically injected 15 minutes prior to eating a meal, or immediately after eating.
Brand name Humalog products
The maker of Humalog insulin, Eli Lilly and Company, produces this medicine in three forms:
- Humalog: This liquid solution is available at a concentration of 100 U of insulin lispro per mL.
- Humalog Mix75/25™: In this mixed formulation, Humalog is mixed with NPH (neutral protamine Hagedorn), an intermediate-acting form of insulin, at 75% NPH, 25% insulin lispro.
- Humalog Mix50/50™: This mix is composed of 50% NPH, 25% insulin lispro.
Each form is available in a vial or in an insulin pen (such as a KwikPen™), which is a portable, pen-like injectable device contains the liquid Humalog. The pen can deliver an as-needed dose and is ready for injection. Importantly, mixed or diluted humalog should not be used in insulin pumps.
Possible Humalog side effects
The possible side effects of insulin lispro are similar to those from natural human insulin.
- Hypogycemia. The most common side effect is hypoglycemia (low blood sugar). Mild to moderate hypoglycemia is treated with eating a sugary food immediately. Severe hypoglycemia requires medical attention and can cause seizures and/or coma.
- Anaphylaxis (severe allergic reaction). The symptoms of anaphylaxis include swelling of the throat and/or tongue, trouble breathing, and a rapid heart rate. Anaphylaxis should be immediately treated by medical professionals.
Other side effects include low blood potassium levels, pitting of the skin at the injection site, and/or weight gain
Eli Lilly, "Humalog"
Eli Lilly, "Full Prescribing Information"
Eli Lilly, "About Humalog KwikPen"
National Library of Medicine, "Insulin Lispro Injection"