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Levemir vs Lantus: What's the Difference?

Medically reviewed by Last updated on Aug 4, 2022.

Levemir and Lantus are both types of insulin. But which one works for longer and which one has fewer side effects?

Official answer


Levemir (detemir) and Lantus (glargine) are both long acting insulins and no difference has been found in their efficacy however, weight gain and night-time hypoglycemia appear to be less with Levemir.

Other differences:

  • Some studies dosed Levemir twice daily; however, at least one study has found this makes no difference to HbA1c control and concluded that Levemir was just as effective if dosed once daily like Lantus is.
  • Levemir may cause more injection site reactions compared with Lantus; however, Lantus may have more of a detrimental effect on mitochondria.
  • Both are available as vials or cartridges and cost is similar although Lantus is often discounted. Levemir lasts for 42 days once opened, Lantus for 28 days.
  • They should not be used together but are usually included in a regimen with short or rapid-acting insulins. Although both Levemir and Lantus are long-acting insulins, one should not be substituted for the other except on a doctor's advice.

Levemir Vs Lantus: Both human insulin analogs

Levemir is a brand name for insulin detemir. Levemir takes at least one hour to start working (some sources state up to three hours), and its effects are dependent on the initial dosage given. Dosages of 0.1 units per kg may last only six hours whereas dosages equal to or greater than 0.8 units/kg last approximately 22 to 24 hours. Levemir has a relatively peakless profile but may be more slowly absorbed from the thigh compared to the deltoid (arm) and the abdomen after subcutaneous administration.

Lantus is the brand name for insulin glargine. Lantus takes approximately an hour to start working and lasts for an average of 24 hours; however, there is some variability and in some people, it may only act for just over 10 hours, whereas for others it may last longer than 24 hours. Lantus releases consistently, so doesn't really have a peak effect.

Levemir Vs Lantus: Differences in formulation account for some differences in action

Both Levemir and Lantus are made by modifying human insulin. Both should be clear solutions before they are injected (discard if cloudy).

Insulin glargine (Lantus) tends to be absorbed more slowly and for longer than detemir ( Levemir) because it is not as soluble once injected just under the skin. This means it has a longer duration of action and an insignificant peak effect - instead, it delivers consistent blood levels of insulin.

Insulin detemir (Levemir) remains soluble after injection but is able to bind to protein in the tissue and bond to itself which gives it a prolonged action.

How do Levemir and Lantus compare to NPH insulin?

Both Levemir and Lantus were created to improve on NPH insulin, and to better mimic a person without diabetes's normal physiological basal insulin release. Both Levemir and Lantus are preferred over NPH insulin because they have a longer duration of action, a less pronounced peak, and are more consistent in their effects with less risk of hypoglycemia. Both Levemir and Lantus are clear solutions, unlike NPH which requires resuspension prior to injection.

However, neither Levemir or Lantus perfectly mimic normal basal insulin release.

Studies that have compared Levemir and Lantus to NPH have reported almost identical effectiveness in long-term HbA1C control. The rates of symptomatic hypoglycemia were lower with glargine; however, overall hypoglycemia was lower with detemir. Both glargine and detemir reported lower night-time hypoglycemia compared with NPH.

Levemir Vs Lantus: head to head studies

Only a few trials have directly compared detemir (Levemir) to glargine (Lantus). No significant differences in effect were reported in a trial by Pieber et al that compared twice daily detemir to once-daily glargine. The risk of severe or night-time hypoglycemia was not as great with detemir. The total average daily dose of detemir was higher than that of glargine.

Slightly less weight gain was reported in a study by Rosenstock et al with detemir compared with glargine (3.0kg vs 3.9kg) when detemir once or twice daily or glargine once daily was given as add-on therapy to people with type 2 diabetes. This finding was backed up by another study by Hollander et al that reported weight gain with detemir was 2.8kg versus 3.8kg with glargine. Interestingly, this study found no difference between giving detemir once daily or twice daily. Neither study found any difference between detemir and glargine with regards to efficacy.

Levemir Vs Lantus: Side effects and interactions

Detemir (Levemir) is more likely to cause injection site reactions compared with glargine (Lantus) and more people are likely to discontinue treatment with detemir compared with glargine (21% versus 13%).

Detemir appears less likely to cause weight gain than glargine.

Despite the fact that detemir binds to protein, significant drug interactions are unlikely. Some mitochondrial studies have suggested that glargine has more of a detrimental effect on mitochondria than detemir.

Although some studies have suggested insulin analogs increase the risk of certain types of malignancies, these studies were poorly conducted so it is still unknown how much of a risk insulin poses. Both the American Diabetes Association and the American Cancer Society have acknowledged that people with diabetes who use insulin do appear to be at increased risk. More trials are needed.

All insulins should be used cautiously and dosed conservatively in people with renal or hepatic impairment. Neither detemir nor glargine appears to have different responses in different ethnic groups.

Levemir Vs Lantus: Formulations and Cost

Both Levemir and Lantus are available as vials and cartridges. Both are suitable for once daily administration (although some studies dose Levemir twice daily). Neither requires resuspension prior to injection.

Levemir costs approximately $291 for a 10ml vial containing 100 units/ml of Insulin detemir ($29 per ml). Lantus costs approximately $135 for a 10ml vial containing 100 units/ml of Insulin glargine ($13.54 per ml); however, cost can vary up to $27 per mL. Neither Levemir nor Lantus has a generic version. Both require refrigeration until opened. Once opened, pens and vials may be stored out of the fridge. Levemir lasts for 42 days once opened, Lantus only lasts for 28 days.

See also: Compare Tool - Lantus vs Levemir

General Facts About Insulin

  • Do not freeze any insulin. Throw insulin out that has been mistakenly frozen.
  • Keep insulin away from direct sunlight or heat
  1. Types of Insulin for People with Diabetes Joslin Diabetes Center
  2. Lantus (Insulin Glargine) [Package Insert] Revised: 08/2015 sanofi-aventis U.S. LLC
  3. Levemir (Insulin Detemir)[Package Insert] Revised:02/2015 Novo Nordisk
  4. Swinnen SG, Simon ACR, Holleman F, et al. Insulin detemir versus insulin glargine for type 2 diabetes mellitus. Cochrane Database of Systematic Reviews 2011, Issue 7. Art. No.: CD006383. DOI: 10.1002/14651858.CD006383.pub2.
  5. Poon K, King AB. Glargine and detemir: Safety and efficacy profiles of the long-acting basal insulin analogs. Drug, healthcare and patient safety. 2010;2:213-223. doi:10.2147/DHPS.S7301.
  6. Rosenstock J, Davies M, Home PD, et al. A randomized, 52-week, treat-to-target trial comparing insulin detemir with insulin glargine when administered as add-on to glucose-lowering drugs in insulin-naïve people with type 2 diabetes. Diabetologia. 2008;51:408–416.
  7. Pieber TR, Treichel HC, Hompesch B, et al. Comparison of insulin detemir and insulin glargine in subjects with type 1 diabetes using intensive insulin therapy. Diabet Med. 2007;24:635–642.

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