Type of insulin	Onset	Peak level	Effective duration
Lispro (Humalog)	5 to 15 minutes	30 minutes to 1.5 hours	3 to 5 hours
Regular (Humulin R, Novolin R)	30 minutes to 1 hour	2 to 3 hours	3 to 6 hours
NPH (Humulin N, Novolin N)	2 to 4 hours	4 to 10 hours	10 to 16 hours
Lente (Humulin L, Novolin L)	3 to 4 hours	4 to 12 hours	12 to 18 hours
Ultralente (Humulin U)	6 to 10 hours	None	18 to 20 hours