Building Competency in Diabetes Education THE ESSENTIALS

BASAL-BOLUS INSULIN THERAPY | 12-96

carbohydrate:insulin ratio =

g carbohydrate # units insulin at baseline dose

Example:

= =

52 g

Lunch carbohydrate Lunch insulin dose

7 units rapid-acting insulin

Ratio: 52 g carbohydrates 7 u insulin

or 7.4 g carbohydrates per unit of insulin

Note: When establishing the ratio, it may be advisable to round up to the nearest whole number, regardless of the decimal value. By doing so, the insulin will cover a greater amount of carbohydrate, less insulin will be taken, and there is less likelihood of having a low BG. For this example, 8 g of carbohydrate will be covered by 1 unit of insulin, or 8:1. Example: Carbohydrate intake = 56 g

vs.

When the ratio is 8:1, less insulin is taken for the same amount of carbohydrate. • It is important to remember that a carbohydrate:insulin ratio must be calculated for each time that rapid- or short-acting insulin is taken. Insulin requirements during the day will change based on counterregulatory hormone levels, degree of insulin resistance and level of physical activity. Therefore, the carbohydrate:insulin ratio may be different for each time that rapid- or short-acting insulin is taken. As well, a person’s insulin requirements may change over time, at which point a new baseline insulin dose will need to be calculated. This means that the carbohydrate:insulin ratio will also require recalculation.