Query: What type of insulin is Humalog?
Context: Humalog (insulin lispro) is a fast-acting insulin. It begins working to lower blood sugar levels about 15 minutes after injection, reaches a peak in about 1 hour, and continues to work for 2 to 4 hours. Humalog helps to control the blood sugar spikes that may occur during mealtime. It is used within 15 minutes before eating or right after eating a meal.