Maintaining a normal blood sugar level is important for the healthy functioning of the body. Certain health conditions cause abnormally high blood sugar, and if left untreated, this can lead to very serious health consequences. Too much glucose in the blood can damage the blood vessels leading to an increased risk of heart disease, a heart attack or stroke. It can also cause damage to the kidneys and nervous system, and weaken the immune system that further causes impaired wound healing. Diabetes is a disease characterized by abnormally high blood sugar levels that cannot go down without treatment. In diabetes, the pancreas cannot produce insulin at all (type 1 or 2 diabetes) or it cannot produce enough insulin (type 2 diabetes) to process the glucose in blood so that it can be converted into energy within our cells. Instead, the glucose remains in the bloodstream causing high blood sugar levels.
Diabetes is not a curable condition, but it can be managed with treatment and lifestyle changes. According to the Centers for Disease Control and Prevention (CDC), normal fasting blood sugar is under 99 mg/dL, whereas fasting diabetic blood sugar level is higher than 126 mg/dL. It is important to regularly screen blood glucose levels during check-ups with your doctor to monitor whether you are at risk for diabetes. Type 1 diabetes is usually diagnosed early during youth so it is also called juvenile diabetes. Type 2 diabetes can be diagnosed at any age, although it is more common in adults. A blood sugar level between 100-125 mg/dL can indicate prediabetes, and with certain lifestyle changes it can be prevented from developing into type 2 diabetes. Since in both type 1 and 2 diabetes the body cannot make insulin itself, diabetic patients have to take artificial insulin for the rest of their lives. Most of the time, diabetic patients are given one type of insulin that works throughout the day, and another insulin that can process quick rises in blood sugar levels after eating (also called ‘bolus insulin’).
Humalog and Novolog
Two of the most commonly used biosynthetic insulin drugs are Humalog and Novolog. Humalog and Novolog are both rapid-acting insulin, meaning that they begin to work about 10 to 15 minutes after administering it and they peak after one hour. Rapid-acting insulin is used to help maintain blood sugar levels during mealtimes. In contrast, regular insulin reaches the bloodstream about 30 minutes after injection and their levels peak 2 to 3 hours later. Long-acting insulin takes many hours to reach the bloodstream but its effects remain for up to 24 hours after injection. Now let’s answer the question: what is Humalog? Humalog insulin was first approved for use by the Food and Drug Administration (FDA) in 1996 and Novolog was FDA-approved in 2000. Humalog is also known as ‘insulin lispro’ and Novolog is known as ‘insulin aspart’. Both drugs now have generic forms available on the market.
Although both Humalog and Novolog may seem similar, they are different drugs types of medication and cannot be substituted for each other. They have many similarities and a few differences that are outlined here.
Similarities between Humalog and Novolog
Both are used for treatment of type 1 and 2 diabetes
Humalog and Novolog are both indicated for the treatment of type 1 or type 2 diabetes. Novolog is prescribed more generally for both types of diabetes, whereas Humalog insulin is more commonly prescribed for type 1 diabetes, although it is prescribed for type 2 diabetes as well. Both Humalog and Novolog are also used to treat gestational diabetes, or diabetes that occurs in pregnant women. This is an off-label use for these drugs.
Administration method and formulation
Both Humalog and Novolog are administered into the body through injection under the skin. Injection sites can be in the arms, thighs, buttocks or stomach. Humalog is available as 3 mL or 10 mL vials or 3mL cartridges or prefilled pens, and all formulations have 100 units/mL of insulin in them. Novolog also comes in 10 mL vials or 3 mL cartridges or prefilled pens of 100 units/mL of insulin each. Humalog also has a 200 units/mL prefilled insulin pen formulation.
Both Humalog and Novolog are rapid-acting insulin. Research has shown that rapid acting insulin works better in controlling blood glucose levels before or after a meal. They take about 10-15 minutes to start working and peak at 1 hour after injection. The effects last for 2 to 3 hours after injection. Humalog should be injected 15 minutes before a meal, and Novolog should be injected 5 to 10 minutes before a meal.
Similar side effects
The reported Novolog or Humalog side effects are generally similar. They can both cause low blood sugar, or hypoglycemia, if too much insulin is taken. Using either insulin can also cause weight gain, nausea, diarrhea, headache or stomach ache. Sore throat and muscle weakness have also been reported to occur with Humalog and chest pain has been associated with Novolog.
Similar drug interactions
Humalog and Novolog both have the same risk of drug interactions. Other anti-diabetic drugs, like glipizide, glyburide, repaglinide, and nateglinide that are combined with either Humalog or Novolog can increase the risk of hypoglycemia. Corticosteroids like prednisone or dexamethasone that increase glucose levels in the blood can decrease the effect taking insulin. Both anti-psychotics, like clozapine, and diuretic drugs, such as hydrochlorothiazide can increase the risk of insulin resistance. Taking beta-blockers while on insulin can also interfere with recognizing the signs of hypoglycemia if it occurs, which can be extremely dangerous. If you are taking any of these medications, make sure you inform your doctor.
Differences between Humalog and Novolog
Humalog and Novolog are both synthetic human insulin but they have slight differences in their amino acid composition that gives them a better absorption rate compared to natural insulin. Human insulin naturally consists of two polypeptide chains that are joined together. In Humalog (insulin lispro), the last two amino acids of the B chain, lysine and proline have been switched in position, moving proline to position 28 and lysine to position 29. In Novolog, position 28 of the B chain contains aspartic acid instead of proline. These changes allow Humalog and Novolog to reach peak concentrations faster than regular insulin because it allows more insulin monomers to be available for controlling blood sugar levels after a meal (postprandial glucose) when they are injected.
Time it takes to act
Both drugs are fast acting insulin. However, Novolog starts to work a little faster than Humalog after injection. Novolog starts it effects about 5 to 10 minutes after injection, whereas Humalog takes up to 15 minutes to start working. Therefore, it is recommended that Novolog is administered 5 to 10 minutes before eating a meal or soon after you start eating a meal, and Humalog is best administered 15 minutes before a meal or right after the meal is finished. Both take the same amount of time to reach their peak concentration (1 hour) and their effects last for the same amount of time (2 to 3 hours).
Both Humalog and Novolog are recommended for adults with type 1 or type 2 diabetes. They differ in the age recommendation for children with type I diabetes. Humalog is recommended for children with type 1 diabetes that are above the age of 3 years, whereas Novolog can be used by children with type 1 diabetes that are 2 years of age or older.
Which one is better? How to choose and save
The cost of Humalog and Novolog will largely depend on your health insurance plan and the formulation that you get, but their prices are mostly similar and averages around $300 for a 10mL vial. Humalog is slightly cheaper. Both drugs now have generic forms on the market now as insulin lispro and insulin aspart that makes the drug more affordable at half the cost of the brand-name version. In general, the cost of buying insulin has been increasing over the past few years in the U.S, and even with insurance plans that have prescription drug coverage, the cost of buying insulin can be quite steep. You can find additional savings on Humalog or Novolog through drug coupons available here. The discounted price using the coupon could be cheaper than your insurance plan. Since insulin is a drug that must be used regularly, using a free pharmacy discount card to get regular savings on the drugs can also help you substantially reduce the costs of buying it.
Overall, both Humalog and Novolog are types of fast acting insulin that work to lower blood sugar levels after eating. Research has shown that both drugs are equally effective in controlling blood sugar levels after meals and they work better than long-acting insulin for this purpose. The main difference is that Novolog works slightly faster than Humalog, but the effect of both drugs last for the same amount of time. Your doctor can help you decide which insulin is better for you by considering other types of insulin or drugs you may be taking to choose the one that is likely to be the best fit with your diabetes treatment plan.
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Diabetic.org is devoted to producing expert and accurate articles and information for our readers by hiring experts, journalists, medical professionals, and our growing Diabetic.org community. We encourage you to read more about our content, editing, and fact checking methods here. This was fact checked by Erik Rivera and medically reviewed by Dr. Angel Rivera.
Owner, entrepreneur, and consumer health enthusiast.