The primary activity of insulin including Humalog Mix50/50 is the regulation ... Do not reuse or share pens, needles, cartridges, or syringes between patients, even if the needle is changed.

Insulin lispro, the rapid-acting component of Humalog Mix75/25 ... Do not reuse or share pens, needles, cartridges, or syringes between patients, even if the needle is changed.