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Which type of insulin has the longest duration of action?

Medically reviewed by Drugs.com. Last updated on April 4, 2024.

Official answer

by Drugs.com

The insulin that has the longest duration of action, which is the length of time it works, is usually either the intermediate-acting insulins such as NPH insulin (human), or the long-acting insulins such as insulin glargine (Lantus) or insulin determir (Levemir). Their duration of action can be up to 24 hours long.

Intermediate insulin is often combined with rapid or short acting insulins and is usually dosed twice a day. Intermediate insulins cover blood glucose elevations when rapid-acting insulins stop working.

Long-acting insulins lower blood glucose levels when rapid-acting insulins stop working and are used once or twice a day. Insulin glargine (Lantus) is used once a day and is always given at the same time, regardless of meals. Insulin detemir (Levemir) is used once or twice a day, also without regards to meals.

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Both Toujeo and Lantus are long-acting insulins that contain glargine, however Toujeo is more concentrated containing 300 units per mL of glargine, compared to Lantus’s 100 units per mL. When you take this into account the cost of Toujeo and Lantus works out approximately the same (real cost value $30.76/mL for Toujeo compared with $30.23/mL for Lantus). Continue reading

How and where should I inject insulin?

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Can Trulicity be used with insulin?

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