Humalog Vs Novolog


Diabetic patients take various forms of insulin on a regular basis. One of these forms is called rapid acting insulin. This type of insulin takes its effect within minutes. Currently, the two of the forms available on the market are Lispro (Humalog) and Aspart (NovoLog).

These can be used for both Type I and Type II diabetic patients. Patients must always be aware of their need for proper diet and exercise for increased function in treatment. Also, appropriate meal times and promotions are extremely important when receiving regular insulin.

Unlike oral medications, these insulins provide rapid relief of high glucose levels. They are usually prescribed on a sliding scale meaning the dosage depends on the current insulin levels. These sliding scales differ from patient to patient depending on weight, activity level, and age.

Regular insulin usually lasts for 2-4 hours and reaches their peak after one hour. It is important to check glucose levels before and after administering this type of insulin. These levels, as well as the dosage,  applied, should be kept in a record by the patient.  (5)

It is very important that the patient realizes that regular insulins will need to be used in combination with various other treatments including and not limited to Oral medication, diet, exercise, and long lasting insulin. (1-10)

Difference between Humalog and Novolog

Humalog (Lispro)

Below is the image of a vial of Humalog insulin. Patients should pay close attention to the markings and read the insulin vial before administering to help prevent administration errors.

Humalog (Lispro) insulin

a. Humalog was introduced in 1996 and has been proven safe for use when used correctly.  It allows for mealtime injection and close regularization of glucose levels.
structure of Lispro (Humalog)This image shows the structure of Lispro (Humalog). (3)

b.  A negative aspect of Humalog is that the effect is of short-term glucose control.  (4) Also if administered and mealtime is delayed hypoglycemia can occur. IT should be administered 15 min before meals and the patient should assure that the meal is taken.

c. Both adults, as well as children over the age of 3years old, can use Humalog.

d. The forms available include the following: 3 ml cartridges, 3 ml “KwikPen” prefilled, 3ml vials, 10ml vials. (5)

  • The KwikPen cartridges should only be used inside the pen and the insulin inside should never be taken out and administered by other means. (7)

e. Patients should pay close attention to indications noted on insulin pumps. They should never use diluted insulin in the pump.

NovoLog (Aspart)

a. Studies have shown that Novolog has a shorter peak time as other regular insulins whereas others may have a shorter onset. It was also noted that Novolog showed a better postprandial glucose control. Although it shows these improvements it still does not exactly mimic natural insulin.  (1)

b. Its functions and usage are basically the same as Humalog as it lowers glucose levels. It also can cause hypoglycemia if the patient receives their dosage without eating. It is safe for usage in adults and children as young as 2 years of age. Its onset happens in five to ten min after dosage.

c. The forms available are as follows:

  1. 3ml FlexPen
  2. Flex touch and PenFill
  3. 10 ml vials.

iv. Below you will see images of the different forms it is available. Patients should always pay close attention to the information and names of the medication being used to avoid errors in administration.

Novolog flexpen

novolog penfill

insulin aspart Novolog

d. An interesting aspect of Novolog is that it has a diluting medium if a lower dose is needed.  (5)

e. In IV use the concentration should be 0.05-1 unit/ml always using PVC infusion bags. If using subcutaneous pumps, be sure to change the reservoir every 6 days and the material or infusion set every 3 days. Never use mixed or diluted insulin in a pump. (11)

Common Side effects

a. As stated above, both can cause hypoglycemia if used without the intake of a meal. Glucose levels should be closely monitored when receiving either of these insulins.

b. Side effects can be increased or decreased depending on the patient’s diet and exercise habits or even their stress levels.

c. These effects consist of and are not limited to the following:

  1. Nausea
  2. Weight gain
  3. Diarrhea
  4. Headaches

d. Also, an allergy to the medication may be noted with symptoms such as:

  • a rash of any kind
  • itchiness
  • difficulty breathing and irritability

If you notice any of these symptoms, be sure to alert your doctor immediately. (5)


For many years Insulin had a low patient cost thanks to insurance and or Medicare coverage. Recently with changes in health care, cost coverage changes many patients are seeing an increase in the cost of their treatment. The situation can be very difficult for doctors to understand and even more so for patients to deal with.

This is because everyone has a different form of payment and insurance coverage. Dr. Hirsch is noted to say that as of five years ago he paid $20 for the amount of insulin needed for three months. And now he is paying $150 for the same amount of insulin.

Below you will see a chart that shows all the types of insulin that are currently in use. The first couple named is Humalog and Novolog. They are grouped together as regular insulin or fast-acting insulin. As you can see in the graph their reactions are very similarly especially compared to other insulin types.

References :


Published by Dr. Rajesh MD under Diabetes Information.
Article was last reviewed on January 8th, 2022.

Leave a Reply

Back to Top