Each Insulin type works at a different pace, and most people have to use more than one kind to mimic their actual bodies system.
Insulin time factors
Before get into the details on insulin types, it is better to know about-three time factors about insulin they are
- Onset time – insulin requires certain time to start lowering blood-glucose.
- Peak time - the time, at which insulin works to its best (peak or maximum power) to lower the blood-glucose.
- Duration time - length of time the insulin works to keep lowering blood-glucose.
Each type of insulin works at a different onset, peak, and duration time as per specific requirement.
Insulin types
Based on the above-said insulin time factors, insulins are classified into three main categorical types; they are
- Rapid-acting insulin,
- Short-acting insulin,
- Intermediate-acting insulin,
- Long-acting insulin,
- Very long-acting insulin.
Rapid-acting insulin type
This is the fastest insulin of all. Once injected, it starts to work within 15 minutes (onset time). It works to its maximum (peaks time) at about an hour after injection and usually used up in four or five hours (duration time). This type of insulin is for injecting right before meals. By the time, the meals are digested and release glucose into the bloodstream, rapid-acting insulin is working to its peak and makes cells to consume glucose. Rapid-acting insulin is looks clear in appearance.
Short-acting insulin type
Otherwise, it is called as "regular" insulin, which can be useful around mealtime. It takes longer to work (onset time) than rapid-acting insulin. So take short-acting insulin about 30 to 45 minutes before having meals, and it works to its maximum (peak time) at about two or three hours. It can keep working for as long as six hours (duration time). Short-acting insulin is looks clear in appearance.
Intermediate-acting insulin type
This insulin is designed is such a way to make the body absorb the insulin more slowly. It takes longer to start to work, and it stays in the body for a lengthy time. This type has approximate onset time of 2 to 4 hours, peak time of 4 to 12 hours, and duration time of 12 to 18 hours. Intermediate-acting insulin works all day if taken in the morning. This insulin type looks cloudy and is needed to mix by shaking before injected.
Long-acting insulin type
It starts to work in six to 10 hours (onset time) and can stay in the body for 20 hours or more (duration time). It does not have any peak time at all. It is useful to take in the morning or before bed, like intermediate-acting insulin. Long-acting insulin is looks clear in appearance.
Very long acting insulin type
There is also glargine insulin, which is very long-acting insulin. It starts to lower blood-glucose levels about 1 hour after injection, and keeps working for 24 hours.