Lispro
- It is a semisynthetic analog of human insulin.
- It is identical to human insulin except for the transposition of proline and lysine at positions B28 and B29 in the B chain.
- When it is injected s.c, it dissociates quickly into monomers and is rapidly absorbed.
- Onset of action 5-15 min.
- Peak activity in 1 hr.
- Duration of action 3-5 hrs.
- (i.e., rapid onset and short duration).
Aspart
substitution of the B28 proline with a negatively charged aspartic acid. When they are injected subcutaneously, the drugs are rapidly absorbed with onset of action within 5–15 minutes, and reaching peak activity as early as 1 hour⇒ short duration of action.