Insulin Lantus: What is it? How does it work? Indications, Administration, Benefits, Side Effects and Interactions

Sanofi-Aventis produce it under the medical name insulin glargine.

What is Lantus insulin?

It is an ultra-lens (long-acting) insulin analog. Lantus’ medical name, insulin glargine, is taken from how the DNA of human insulin is modified to form the analog.

In the case of glargine, glycine and the two arginines are part of the genetic recombination that helps make insulin.

How does Lantus insulin work?

Insulin is the key that unlocks your cells, allowing the sugar in your bloodstream to pass into your cells. This gives them the energy they need to do their various jobs. As a result, blood sugar levels drop.

Lantus insulin is considered basal insulin. It is in the extended acting class and is given once a day. It is injected as a clear liquid but then forms small particles inside the body.

These particles dissolve slowly, releasing the medication evenly over time.

Lantus insulin works slower than natural insulin and therefore allows for a much more stable blood sugar level over 24 hours.


Since Lantus continues to work for 24 hours, most people should inject at the same time of day.

In general, Lantus starts working about an hour or two after the injection, peaks in six hours, and continues to work for 18 to 26 hours.

However, they are all different. For some people, Lantus does not last a total of 24 hours, so they see higher glucose numbers a couple of hours before injection time.

Others find that Lantus lasts longer for them, so the dose from the day before can still work for a couple of hours after the injection time.

It is a good idea to check your blood sugar level frequently while adjusting to Lantus. Learn how it works in your body, and then you can talk to your doctor about making adjustments, if necessary.

Who is prescribed Lantus insulin?

Lantus insulin can be prescribed for all types of diabetes. However, it is most commonly prescribed to people with type 1 diabetes.

Lantus insulin can be prescribed to people with type 2 diabetes for whom oral hypoglycemic agents are not effective enough.


Lantus insulin is injected, usually once a day at the same time every day. Like all insulins, Lantus must be injected subcutaneously (into the fatty tissue under the skin).

Lantus’ specific mode of action should never be diluted or mixed with any other insulin before injecting.

Benefits of Lantus insulin

Lantus mode of action allows for a peakless profile. Lantus has become popular prescription insulin, as its constant activity can help reduce nighttime hypoglycemia.

Side effects

The most common side effect of Lantus, or any insulin, is hypoglycemia (or low blood sugar). Knowing the signs of hypoglycemia and how to treat an episode quickly is essential.

Low blood sugar can lead to unconsciousness and even death if not treated properly.

Make sure your family members and caregivers know what to look for and how to manage a low blood sugar problem in case you cannot help yourself or miss symptoms.

Being insulin, hypoglycemia can be a relatively common side effect of using Lantus if the doses are too strong. Other side effects include allergic reactions and swelling, itching, or pain at the injection site.

Lantus insulin is the brand name for synthetic insulin glargine, an injectable form of insulin designed to help people with diabetes lower their blood glucose levels.

Sanofi-Aventis manufactured Lantus insulin. Since Lantus’ patent expired in 2015, other biosimilar versions of insulin glargine have been hitting the market (such as Toujeo from Sanofi and Basaglar from Lilly).

Other possible side effects associated with Lantus include:

Allergic Reaction: Although a severe allergic reaction to Lantus is rare, it is still possible. Tell your doctor if you experience any of the following symptoms:

  • Eruption.
  • Itch.
  • Swelling.
  • Severe dizziness
  • Difficulty breathing.
  • Difficult breathing
  • Fast heartbeat
  • Swelling of the face, tongue, and throat.
  • Short of breath.
  • Perspiration.
  • Extreme drowsiness, dizziness, or confusion.
  • Weight gain.

Low potassium levels – Symptoms include:

  • Muscle cramps.
  • Weakness Irregular heartbeat.
  • Injection site reactions, including tissue damage.
  • Nose, sinus, or throat infection.
  • Low blood pressure.
  • Visible water retention.

How should Lantus insulin be used?

Lantus insulin is available in pre-filled devices known as SoloSTAR Pens. It is also sold in a vial to be administered with a syringe. Lantus should NOT be used in infusion pumps as it could cause severe hypoglycemia.

When injecting Lantus, be sure to inject under the skin in a fatty area, such as the abdomen, thigh, or triceps (back of the arm). Insulin should not be injected into arteries, veins, or muscles.

Some experts recommend rotating your injection sites to avoid causing tissue damage by repeatedly injecting at the same site.

Others recommend rotating sites within the chosen injection area, but NOT rotating sites because insulin is absorbed in different rates in each of the three areas:

  • ABS.
  • Thighs
  • Upper arms.

Talk to your doctor and follow their guidance regarding rotary injection sites.

For people with type 1 diabetes and those with type 2 diabetes who use insulin, sometimes Lantus insulin is insufficient to maintain stable blood sugar levels throughout the day. It would help if you had boluses at mealtime with a bit of extra insulin.

Your doctor may prescribe short-acting insulin to use with meals, which will work with your long-acting Lantus insulin to keep your levels under control at all times.

Who should not take Lantus insulin?

If you are allergic to insulin glargine or other ingredients in this medicine, do not take Lantus.

Lantus may not be the correct medicine for you if you are pregnant or breastfeeding. Studies have not yet been done to determine if Lantus is safe for unborn babies.

It is also not known whether this insulin can pass into breast milk. However, if it can, it probably will not harm the baby, as insulin cannot survive in the digestive tract (which is why we cannot take oral insulin).

Talk to your doctor about the benefits and risks of taking Lantus during pregnancy and while breastfeeding.

Tell your doctor if you have liver or kidney disease.

What medications can interact with Lantus insulin?

Many medications and vitamins, supplements, and supplements can influence the effectiveness of insulin, so be sure to provide your doctor and pharmacist with a complete list of everything you take.

They can tell you if any are contraindicated for use with Lantus insulin or any other insulin.

If you are taking any of the following medications, you should know that you may not be able to detect an episode of hypoglycemia:

  • Albuterol.
  • Clonidine.
  • Reserpine.
  • Betabloqueantes (como atenolo, carvedilol, labetalol, metoprolol, nadolol, propranolol, sotalol, etc.).