Lantus Vials (insulin glargine)

100u/mL/10mL – 1 Vial

Lantus Cartridge 100 Units / mL

100u/mL – 5 cartridges

What is Lantus® (insulin glargine injection)?

Insulin is a hormone that is naturally produced in our body that works by lowering blood sugar (glucose) levels in the blood. For those who do not produce enough insulin require taking an insulin analog which is a man-made form of insulin.

Lantus is a brand name of insulin glargine taken by adults and children at least 6 years of age with type 1 (insulin-dependent) or type 2 (non insulin-dependent) diabetes.

Lantus is known as a basal insulin (or baseline) which is slowly released evenly throughout the day without spikes as seen with other insulin analogs.

A Lantus treatment may sometimes need the support of a bolus insulin or fast-acting insulin that reduces blood sugar spikes after meals.

This long-acting insulin is injected under the skin (subcutaneously) and helps manage blood sugar levels. It’s formulation of micro-crystals slowly release insulin and provide patients a steady and long-term baseline that starts to work after several hours and works continuously up to 26 hours.


A side effect is any unwanted response from taking medication in regular doses.

Side effects associated with taking Lantus can range from mild to severe. The lists below do not cover all possible side effects. If you are concerned about the potential risks of taking this medication, speak to your doctor.

Seek medication attention immediately if you experience:

  • redness or swelling
  • itchy rash all over your body
  • difficulty breathing
  • swelling of the tongue and throat
  • rapid heartbeat
  • feeling like you may lose consciousness

Consult your doctor if you are experiencing:

  • swelling of hands and feet
  • feeling short of breath
  • weight gain
  • signs of low potassium (leg cramps, irregular heartbeat, increased thirst or urination, muscle weakness or feeling limp, numbness or tingling, fluttering in your chest.

Common side effects from using Lantus include:

  • low blood sugar
  • thickening or hollowing of skin at site of injection
  • mild skin rash
  • itching
  • edema (swelling)
  • respiratory infections
  • hypoglycemia (low blood glucose levels)
  • injection site reactions

These side effects are typically temporary and go away after a few days or weeks. If they don’t go away and become more severe, speak to your doctor or pharmacist.

Serious Side Effects

While serious side effects aren’t common, they can occur. Symptoms can include:

  • allergic reaction
  • abnormal heart beat
  • fatigue
  • Hypokalemia (low potassium levels)
  • weakness
  • muscle cramping
  • paralysis
  • severe hypoglyecemia
  • allergic reactions
  • respiratory failure

Side effects in detail

The following common side effects are associated with Lantus in more detail.

Allergic Reactions

Some may experience allergic reactions when taking Lantus. Make sure you do not have an allergy to any ingredients in this solution.

Mild allergic reactions may include:

  • flushing
  • itchiness
  • skin rash (red and warm skin)

Severe allergic reactions may include:

  • difficulty breathing
  • full body rash
  • swelling of the mouth, tongue or throat
  • swelling under the skin (typically lips, hands, feet or eye lids)

Consult your doctor immediately if you experience any severe allergic reactions while taking Lantus insulin. Call 911 and seek medical emergency if you feel the symptoms are life threatening.

Weight Gain

One of the most common side effects while taking Lantus is weight gain since the body stores sugar for energy. The average weight gained according to clinical studies was:

  • up to 1.5 lb in adults with type 1 diabetes who took Lantus over 16-28 weeks
  • up to 4.8 lb in children with type 1 diabetes who took regular insulin with Lantus for 28 weeks
  • up to 4.4 lbs in adults with type 2 diabetes who took Lantus for 1 year

If weight gain is a concern, speak to your doctor on how to better manage your weight.


Hypoglycemia (low blood sugar) is the most common side effect with any insulin such as Lantus.

It’s important to monitor your blood sugar levels so you can address a hypo before it becomes severe.

Mild hypoglycemia symptoms include:

  • rapid heartbeat
  • shakiness
  • nervousness
  • shakiness
  • dizziness
  • headache
  • hunger

If blood sugar levels remain too low, symptoms may worsen and require medical attention.