Lantus vs. Humalog for Diabetes Type 2 and Diabetes Type 1: Important Differences and Potential Risks.

Key takeaways

Lantus (insulin glargine) and Levemir (insulin detemir) are both long-acting insulins used to manage blood sugar levels in people with Type 1 and Type 2 diabetes. One key difference is that Lantus is typically injected once daily, while Levemir can be injected once or twice daily, depending on your dose and needs. Both Lantus and Levemir come in vials and prefilled pens. Levemir has a lower risk of weight gain compared to Lantus. Both medications can cause low blood sugar and should not be mixed with other insulins. Additionally, Levemir Flexpens have been discontinued as of April 2024 and vials will be discontinued by December 2024. Always follow your healthcare provider's instructions on how to use these insulins properly.

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Levemir Vs. Lantus: How Do They Compare For Diabetes?

Lantus

(insulin glargine)

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Humalog

(insulin lispro)

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Summary for Lantus

Prescription only

Lantus (insulin glargine) is a type of long-acting insulin. It's used to help manage blood sugar levels in people with Type 1 diabetes or Type 2 diabetes. Lantus (insulin glargine) is injected under the skin once daily. Your dose will depend on a few things, such as the type of diabetes you have and your blood sugar levels. This medication comes in a vial (Lantus) as well as in a prefilled insulin pen (Lantus Solostar). Some side effects include upper respiratory tract infections. It can also cause redness and swelling at the injection site.

Indications for Lantus

Type 1 diabetes (T1D)
Type 2 diabetes (T2D)

Pros and Cons for Lantus

Pros

Helps keep your blood sugar controlled for about 24 hours
Injected once daily
Approved for both adults and children
Available as a vial and prefilled pen

Cons

Given as an injection under the skin
Has a risk of causing dangerously low blood sugar
Might cause weight gain
Can't be mixed with other insulins within the same syringe

Common Side Effects for Lantus

Type 1 diabetes

Upper respiratory tract infection (22%)
Other infection (9%)
Accidental injury (6%)
Headache (6%)

Type 2 diabetes

Upper respiratory tract infection (11%)
Other infection (10%)
Eye problem (6%)

Warnings for Lantus

Risk of infection from sharing pens and needles
Risk of changes to blood sugar levels with changes to your insulin routine
Low blood sugar (hypoglycemia)
Low potassium levels
Swelling and risk of heart failure when using with certain diabetes medications
Severe allergic reaction

Summary for Humalog

Prescription only

Humalog (insulin lispro) is a fast-acting insulin for adults and children with diabetes. It helps prevent and treat high blood sugar from meals. This medication lowers your blood sugar levels by moving the sugar from your blood and into your body. Humalog (insulin lispro) is typically given as an injection under the skin. In certain situations, it's injected into the veins by a healthcare provider. Humalog (insulin lispro) is available as vials and ready-to-use prefilled pens. Side effects include headache and low blood sugar (hypoglycemia).

Indications for Humalog

Type 1 diabetes in adults and children
Type 2 diabetes in adults

Pros and Cons for Humalog

Pros

Starts to work within 15 minutes to lower blood sugar levels
Dose can be easily adjusted to make a treatment plan that's tailored to your specific needs
Available as a prefilled pen for easier and convenient use
Can use at home after proper training
Can use in children as young as 3 years old with Type 1 diabetes

Cons

Given multiple times a day (before each meal)
Must give as an injection
Might be hard for some people to take properly
Risk of low blood sugar
Can cause weight gain

Common Side Effects for Humalog

Type 1 diabetes:

Flu-like symptoms (35%)
Sore throat (33%)
Runny nose (25%)
Headache (30%)
Pain (20%)
Cough (17%)
Infection (14%)

Type 2 diabetes:

Headache (12%)
Pain (11%)
Infection (10%)

Warnings for Humalog

Spread of infections from sharing injection supplies
Low blood sugar (hypoglycemia)
Low blood potassium levels
Swelling from fluid buildup and risk of heart failure when taken with certain blood sugar medications
Dangerously high blood sugar levels or buildup of ketones (for people who use insulin pump)