Which insulin is not rapid-acting?

Which insulin is not rapid-acting?

• A. Lispro
• B. Glargine
• C. Humulin R
• D. Detemir

Answer: (C)

Rapid-acting insulins start working quickly after injection, typically within 10–15 minutes, peak around 1–2 hours, and last about 3–5 hours. Regular insulin, such as Humulin R, does not fit that rapid profile—it has a slower onset (around 30 minutes), peaks in roughly 2–4 hours, and lasts about 6–8 hours, making it a short-acting rather than rapid-acting insulin. The other options illustrate clear rapid-acting or long-acting profiles, with lispro being rapid-acting and glargine or detemir being long-acting. Clinically, this difference guides timing: rapid-acting is often given at meals, while regular insulin is typically administered before meals due to its slower onset. Therefore, regular insulin (Humulin R) is the one not rapid-acting.

Rapid-acting insulins start working quickly after injection, typically within 10–15 minutes, peak around 1–2 hours, and last about 3–5 hours. Regular insulin, such as Humulin R, does not fit that rapid profile—it has a slower onset (around 30 minutes), peaks in roughly 2–4 hours, and lasts about 6–8 hours, making it a short-acting rather than rapid-acting insulin. The other options illustrate clear rapid-acting or long-acting profiles, with lispro being rapid-acting and glargine or detemir being long-acting. Clinically, this difference guides timing: rapid-acting is often given at meals, while regular insulin is typically administered before meals due to its slower onset. Therefore, regular insulin (Humulin R) is the one not rapid-acting.