How do my different insulins work?
Basal Insulin (e.g. Humulin I, Insuman
Basal, Lantus, Levemir, Degludec, Toujeo)
If you are on injections, you will take a basal
insulin once or twice a day.
The role of this insulin is to provide 24-hour
cover. This should keep your glucose levels within target range when you
haven't eaten any carbs or taken any quick acting insulin. This means that if
you miss a meal your glucose levels should not rise or fall
If you are on a pump, your background insulin is
given via the pump, controlled by different basal rates through the day and
night
Quick acting insulin (e.g.
NovoRapid, Humalog, Fiasp, Actrapid)
Quick acting insulin has three jobs:
To prevent the rise in your glucose levels after
eating carbs
To correct a glucose reading out of target before
meal time or before bed
To prevent or treat ketones in your blood
You may have been given insulin:carb ratio.
These ratios allow you to work out the correct dose of insulin to cover
carbohydrate food at meal times.
For example, a 1unit:10g ratio suggests you need
- 1 unit of quick acting insulin per 10g of carbohydrate.
What if I need to snack to prevent a hypo?
When you have diabetes, you and the diabetes team
spend a lot of time making sure your doses of insulin are right for you.
If you find your blood sugar levels are dropping
between meals and you have to eat extra even when you don’t want to, it
probably means one of the doses mentioned are not right for you.
What do the patterns in my glucose levels
mean?
Looking at patterns in your blood sugar levels will
help you to work out which dose of insulin might need adjusting.
If you are always dropping low within 4 hours of
taking quick acting insulin with a particular meal, you may need a lower
insulin:carb ratio with that meal.
If you are always dropping low after correcting a
high blood sugar, you may need a weaker correction factor.
If you are always dropping low overnight or more
than 4 hours after taking quick acting insulin, your basal rate or basal
insulin dose may be too high.
Some extra things to consider:
You might also
want to be sure your carb counting is accurate. If you overestimate your
carbohydrate intake, this could also be the cause of a hypo after meals.
If you can’t
work out which insulin needs to change, speak to your diabetes team for some
help.