**CALCULATING YOUR INSULIN SENSITIVITY FACTOR (ISF)**

** **

Your Diabetes Team may use any of the following methods to help find your ISF:

1. **Insulin/Blood Glucose Formula**

(One unit of rapid or short-acting insulin for every 50 mg/dl increase or decrease in your blood glucose level).

2. **Rule of 1500 **– if you are using shortacting insulin (Regular).

3. **Rule of 1700 **– if you are using rapidacting insulin (Humalog®, Novalog®, Apidra®).

**ISF Method I – Insulin/Blood**

** **

**Glucose Formula**

With ISF Method I, you take one unit of rapid or short-acting insulin for every 50 mg/dl increase or decrease in your blood glucose level.

*EXAMPLE:*

*Blood glucose target is 100 mg/dl. *

* *

**John’s pre-lunch blood glucose is 180*** ***mg/dl and his Insulin Sensitivity is 50.*** *

*His reading shows that he is above his target by 80 mg/dl.*

* *

**[180 mg/dl – 100 mg/dl = 80 mg/dl]**

** **

He should take 1 (1.5 if you measure 1/2 units) extra units at lunch.

If his usual dose of rapid or short-acting insulin at lunch were 12 units, he would increase it by one and take 13 or 13.5 units.

*PRACTICE PROBLEMS:*

*Blood glucose target: 100 mg/dl*

* *

**Susan’s pre-lunch blood glucose is 205 mg/dl.**

** **

*Her reading shows that she is above her target by 105 mg/dl*

* *

**[****205 mg/dl – 100 mg/dl = 105 mg/dl]**

** **

**Q **– How many extra units should Susan take?

105 mg/dl **/** 50 = 2 units

**A **– She should take 2 extra units. In this

case she should take a total of 14 units.

***

**CALCULATING YOUR CARB:INSULIN RATIO**

**A carb:insulin ratio** is the amount of rapid or short acting insulin you need to match or “cover” the amount of carbohydrate you eat.

** **

The Rule of 500:

Add up all the insulin given for 24 hours and divide it into 500. The answer is

**your carb:insulin ratio.**

*EXAMPLE:*

Your total insulin dose is 50 units.

500 divided by 50 = 10

Your carb: insulin ratio is 10:1

*Tom’s Calculations:*

Insulin needed for carbohydrates 9 units **(90 carbohydrates divided by 10)**

Insulin needed to correct for high blood glucose **(190-100=90) divided by 30 (ISF)=3**

Total insulin for food and carb** 9 + 3 = 12 units**

Reduction for high intensity exercise (Step 5) **3 unit**

TOTAL amount of pre-dinner insulin **9 units**

*tratament*

joychaos

February 4, 2013

thank you for your blog. such a life saver for those who don’t have insurance or enough money to see a doctor