Specific considerations when insulin is not self-administered
Injector pen devices used with standard pen needles pose a risk of needlestick injury if insulin is administered by another person (eg healthcare worker). If the patient cannot safely self-inject, it is preferable to use pen needles with an automatic safety cover or shield, to minimise the risk of needlestick injury.
If the patient normally uses insulin in a prefilled injector pen and cannot self-inject, and pen needles with an automatic safety cover or shield are not available, obtain the insulin from a cartridge, penfill or vial and administer the dose using an insulin syringe, which is calibrated to 100 units/mL. Do not withdraw insulin from prefilled injector pens and do not use a regular syringe to withdraw insulin from a cartridge, penfill or vial. There is potential for error and an insulin overdose if insulin is withdrawn from a high-concentration insulin prefilled injector pen because insulin syringes are calibrated to 100 units/mL.
If the patient normally uses:
- a 100 units/mL concentration of insulin—change to a cartridge, penfill or vial and withdraw the dose using an insulin syringe
- a high-concentration insulin (glargine 300 units/mL [Toujeo], lispro 200 units/mL [Humalog U200], neutral insulin 500 units/mL [Humulin R U-500])—high-concentration insulins are only available in prefilled injector pens; change to an equivalent dose of a 100 units/mL concentration of the same insulin in a cartridge, penfill or vial, and withdraw the dose using an insulin syringe. It is important to note that doses of insulin glargine 300 units/mL (Toujeo) and insulin glargine 100 units/mL (Optisulin) are not directly interchangeable because they are not bioequivalent—a dose reduction is required to reduce the risk of hypoglycaemia1.