Final answer:
Patients with type 1 diabetes mellitus can inject insulin in the abdomen, upper arms, or thighs.
Step-by-step explanation:
Patients with type 1 diabetes mellitus inject insulin once or several times a day at various sites on the abdomen, upper arms, or thighs. These are the recommended sites for insulin injection as they have a good blood supply and fatty tissue that allows for proper absorption of insulin.
Learn more about sites for insulin injection