Most people with diabetes need at least two insulin shots a day for good blood sugar control. Some people take three or four shots a day to have a more flexible diabetes plan. You should take insulin 30 minutes before a meal if you take regular insulin alone or with a longer-acting insulin. There are five main types of insulin. They each work at different speeds.
Many people take two types of insulin.
Lowers blood sugar most in 45 to 90 minutes. Finishes working in 3 to 4 hours. Lowers blood sugar most in 2 to 5 hours. Finishes working in 5 to 8 hours. Lowers blood sugar most in 6 to 12 hours.