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Yes, it is common to take long-acting (basal) and short-acting (bolus) insulin around the same time, but you should never mix them into the same syringe or injection pen, except in specific, pre-mixed formulations. Most long-acting insulins are incompatible with other types and cannot be mixed.
Taking different insulin types in separate injections
Taking a shot of long-acting insulin and a separate shot of short-acting insulin at the same meal or around the same time is a standard diabetes management practice.
Long-acting (basal) insulin provides a steady dose of insulin over an extended period (typically 24 hours), managing your background blood sugar levels.
Short-acting (bolus) insulin is taken before meals to cover the carbohydrate intake and manage the immediate spike in blood sugar.
Since these two types of insulin have different purposes and functions, it is essential to keep them separate to ensure they work as intended. When injecting separately, use a different syringe or injection pen for each dose and inject into different, rotating sites.
The risk of mixing insulins
Mixing basal insulin (like Lantus or Tresiba) with another insulin in the same syringe can alter its properties and effectiveness, leading to unpredictable blood sugar control.
The long-acting insulin may not be absorbed properly, making its effect less reliable.
The quick-acting insulin's effect may be blunted and delayed.
The exception: Pre-mixed insulins
Some insulins come pre-mixed by the manufacturer with a specific ratio of intermediate-acting and short-acting insulin. These pre-mixed formulas, such as 70/30 or 50/50, are designed to be drawn from a single vial or used in a single pen.
What to do before injecting
If you are unsure about your insulin regimen, always confirm your treatment plan with your doctor or diabetes educator. They can help you understand the types of insulin you are using and the correct procedure for your injections.