The treatment of diabetes often requires insulin therapy. Two of the most popular insulin brands available for treating type 1 & type 2 diabetes are Humulin and Lantus

These insulin brands vary in several respects, and this article will clarify these differences. Let’s begin by defining each insulin, and how they differ from each other:

What is Lantus?

Lantus (insulin glargine) is a long-acting, bio-synthetic (manufactured) form of insulin that only begins to control glucose levels several hours after injection; but then continues to work in a steady manner for up to 24 hours post-injection.

Lantus is used to improve blood sugar control in children with Type 1 diabetes who are six or older, as well as adults with either Type 1 or Type 2 diabetes.   It is important to keep in mind that certain types of Lantus (insulin glargine) are approved only for adults, so it is necessary to consult with your prescribing physician to ensure that the correct insulin is prescribed.

What is Humulin?

Humulin is a naturally occurring analog of human insulin. It is a short-acting form of insulin, acting immediately upon injection.

Humulin is administered by injection to improve blood sugar levels in adults with diabetes. It is important that patients check closely with their prescribing physician to ensure that this is a suitable medication since Humulin is not approved for use in certain patient populations, i.e., anyone under the age of two, or for treatment of type 2 diabetes in children of all ages.

What is the Difference between Humulin vs Lantus?

The main difference between Lantus and Humulin is how long each is actively controlling blood sugar after injection. Lantus remains active for more than 24 hours, whereas Humulin is active for 3-6 hours.

Since both Lantus and Humulin are different versions of insulin, they each may affect a patient differently.

With Lantus, the dosage can be customized for people who have diabetes that is difficult to treat.  In addition, people with chronic liver or kidney problems can also use it.

With Humulin, there is a specific dosing regimen, and there may be different side effects.  It is strongly recommended to consult with the physician to determine which one of these medications is most suitable, based on one’s medical history.

Interactions with other medications

Both Humulin and Lantus interact with albuterol, clonidine, reserpine, guanethidine, or beta-blockers.

It is always important to provide your physician with complete information about which medications you are on, both prescribed and over the counter, as well as herbal remedies and other dietary supplements.



The recommended initial dose of Humulin is 25 mg. once daily in the morning for patients six years old and up.

The dosage may be increased, if needed, by 10-15 mg at minimum intervals of at least five days.


Below is a Lantus Dosing Calculator, provided by Lantus insulin glargine injection 100 units/ml. manufacturer’s insert.

Patients with Type 2 Diabetes Mellitus (T2DM): Lantus dosing

The recommended starting dose of Lantus for patients with Type 2 diabetes who are not currently being treated with insulin is 0.2 Units/kg or up to 10 Units once daily, adjusted to the patient’s appropriate fasting plasma glucose target. The amount and timing of short- or rapid-acting insulins and dosages of any oral anti-diabetic drugs may need to be adjusted

Patients with Type 1 Diabetes Mellitus: Start Lantus at .an appropriate dose for each patient

The recommended initial dose of Lantus should be about 1/3 of the total daily insulin requirements.

Lantus insulin must be used with short-acting insulin.

Key Insulin Administration Instructions


  • Check the insulin label before use to confirm that the correct insulin product is administered.
  • Inspect Humulin visually before use. It should appear clear and colorless.  Do not use Humulin if there is particulate matter or coloration.
  • Protect from heat and light. Do not freeze.  Do not use Humulin after the expiration date printed on the label, or if it had been frozen.
  • About 30 minutes before eating, inject Humulin subcutaneously into the upper arm, abdomen, thigh or the backside.
  • Rotate injection sites within the same area from one injection to another in order to reduce the risk of lipodystrophy syndrome (abnormal deposition of fat at the injection site).
  • Patients using humulin vials must never share needles or syringes. Sharing risks the transmission of blood-borne pathogens and subsequent infection.
  • Whenever there are changes to a patient’s insulin regimen, increase the frequency of blood glucose monitoring
  • Any changes in physical activity, mealtimes, diet, renal or hepatic function, or occurrence of acute illness may require adjustments to insulin dosage.


  • Always check your insulin label every time you take your injection to ensure you are using the correct insulin.
  • Read the detailed “Instructions for Use” package insert for Lantus (insulin glargine) to ensure that you understand proper administration.
  • Adjust the Lantus dosage based on the individual’s metabolic needs, blood glucose levels, and glycemic control goal.
  • You can administer Lantus at any time of the day, as long as it is at the same time each day.
  • Converting from other insulin therapies may require adjusting the timing and dose of Lantus.
  • Closely monitor your glucose values, especially when just converting to Lantus, and during the initial weeks thereafter.
  • Adjustments to the dosage might be needed if there are changes in physical activity, meal patterns, during acute illness, or in kidney or liver function.
  • You can administer doses of Lantus by use of the SoloStar prefilled pen, which also has a built in dose counter. Do not change your dose without first discussing it with your healthcare provider.
  • Lantus pens, syringes, or needles should never be shared with anyone else. Sharing Lantus puts you at a high risk of infection.
  • Never re-use needles. Always use a fresh needle for each injection. The re-use of needles increases the chance of a partial blockage of the needle, which might cause a wrong dose of Lantus. If your needle is blocked, just follow the instructions in Step 3 of the Instructions for Use
  • Lantus is not to be used in an insulin pump or injected into your vein (intravenously).  Lantus should be injected under your skin (subcutaneously).   The best locations are in your upper arm, abdomen, or thigh. Do not ever inject it into a vein or muscle. This can cause severe hypoglycemia (low blood sugar levels) and infections.
  • Rotate the area you choose for the injection of each dose; do not re-use the identical location.
  • Do not mix or combine Lantus with any other type of insulin or liquid medicine.

Advantages & Disadvantages of Lantus


  • Lantus is a long-lasting insulin providing consistent, all-day blood sugar control with just once or twice daily dosing.
  • The dosage can be easily adjusted and tailored to your individual body’s needs.
  • Lantus can be used even with liver or kidney problems.
  • It is available in 2 dosage forms: insulin pen and vial
  • Lantus uses the thinnest (or smallest) needle
  • Once-daily dosing
  • Both vials and insulin pens can be kept at room temperature for 28 days.


  • It is important to maintain a consistent activity schedule to avoid episodes of low blood sugar. Any dramatic changes in weight or meal patterns will require dose adjustments.
  • Lantus is only available as a brand name, so it can be expensive

Advantages & Disadvantages of Humulin


  • Some types of this Humulin are available without a prescription.
  • It is available both as a dose by injection into the fatty part of the skin and as a powder inhaled through the nose.
  • It is available in different combinations so that you have the versatility of choosing one-shot or multiple shots a day.
  • Humulin produced through rDNA technique is similar to that of human insulin, and this reduces the possibility of antibody production and inflammatory response in diabetic patients. It is thus advantageous over conventional types of insulin produced synthetically.


  • Humulin must be taken exactly as directed or it can cause significant hyperglycemic or hypoglycemic episodes.
  • As a short-acting insulin, Humulin must be taken two to three times daily (before meals). This is more frequent than longer-acting insulins, such as Lantus.

Risk Factors


  • Potential for life-threatening low blood sugar (Hypoglycemia), if the insulin dose is too high
  • The accidental use of other blood sugar-lowering medicines at the same time.
  • Poor injection techniques
  • Low potassium (Hypokalemia): Lantus can lower potassium levels in the blood, which can be dangerous. There is already an elevated risk if you are taking other medications that already lower your potassium. It is important to check your potassium levels regularly, and your healthcare provider might then prescribe medications to keep your potassium normal.
  • Allergic Reactions: It is rare, but Lantus can cause severe life-threatening allergic reactions. If you suspect this is happening, go to the emergency room immediately.  Symptoms include sudden problems breathing, a blistering skin rash with a high fever, or if you feel your face, mouth, or throat swell up.


  • Low blood sugar(Hypoglycemia): As with all insulin preparations, the glucose-lowering effect of Humulin is not identical for everybody; it can vary with each individual. This is influenced by many conditions, including the area of injection as well as the blood supply to the injection site.
  • Changes in skin appearance
  • Weight gain: people on Humulin may experience weight gain due to the anabolic effects of insulin.
  • Hypersensitivity and Allergic Reactions: Severe, life-threatening allergic reactions, including anaphylaxis, can occur with Humulin. If hypersensitivity reactions occur, discontinue Humulin; treat per standard of care and monitor until symptoms and signs resolve.  Humulin is contraindicated in patients who have had a hypersensitive reaction to Humulin or its excipients
  • Low Potassium (Hypokalemia): All insulin products, including Humulin, can cause hypokalemia. If untreated, hypokalemia can cause respiratory paralysis, ventricular arrhythmia, and even death. It is important to monitor the potassium levels of patients who are at risk for hypokalemia (e.g., patients using potassium-lowering medications, or patients taking medications sensitive to serum potassium concentrations).

The Takeaway: Which insulin is best for you?

Many factors must be considered when determining which insulin works best for you. Your physician will advise you in prescribing the most suitable type of insulin based on your health, lifestyle, medical history, and ability to maintain a treatment plan.

Factors to consider include:

  • Your physiological response to insulin, i.e., how long it takes your body to absorb the insulin and then how long the insulin continues to control your blood sugar level.
  • Your lifestyle, i.e., the type of food you eat, the amount of alcohol consumed, and the amount of routine exercise, all affect how your body uses insulin.
  • How willing you are to experience multiple self- injections daily.
  • Your age
  • Your commitment to managing your blood sugar.

Your doctor may decide to prescribe more than one type of insulin. You may need to take insulin more than once daily and space your doses throughout the day.