 Insulin dosing
Acronyms and Definitions
 ADA  American Diabetes Association
 Basal Insulin  Long and Intermediateacting insulins used to supply constant blood levels of insulin activity
 Carb  carbohydrate
 DM1  Type 1 diabetes
 DM2  Type 2 diabetes
 FDA  U.S. Food and Drug Administration
 Hypoglycemia  low blood sugar
 Multidose insulin regimen  Insulin regimens that involve a basal insulin and a premeal insulin given at meals
 Premeal Insulin  also called “prandial” insulin. Rapid and shortacting insulins given at mealtime for short burst of insulin.
 Total daily dose of insulin  Sum of premeal and basal insulin given in a day
 Units/kg/day  units of insulin per kilogram of body weight per day
 USDA  United States Department of Agriculture
 1 kilogram = 2.2 pounds
 IMPORTANT POINTS ABOUT DOSING INSULIN
 Overview
 There are a number of different ways to dose insulin
 No detailed guidelines for dosing insulin have been issued by professional associations
 The appropriate method for individual patients will depend on a number of factors including patient education, patient motivation, diabetes control, and resources
 Low blood sugar (Hypoglycemia)
 The main concern in most patients when initiating an insulin regimen is the occurrence of low blood sugars
 Patients need to understand that when they are starting and adjusting insulin, there is an increased risk for low blood sugars
 A number of things can affect this risk including variations in eating patterns, sensitivity to insulin, and variations in activity level
 Measures to help prevent low blood sugars
 Start low and go slow  patients naïve to insulin should start at the lower end of dosing ranges
 When using a multidose regimen, adjust only one of the regimens every 3 days and alternate between the two (see below for more)
 The correction factor can help to keep blood sugars from running too high while the insulin regimen is being adjusted
 Try to avoid insulin doses outside of the regimen as this may lead to overcorrections
 In a multidose regimen, it is important to consume a consistent diet of three meals a day while keeping the number of carbohydrates in each meal about the same
 INSULIN CATEGORIES
 For dosing purposes, insulins can be divided into two categories:
 Basal insulins
 Premeal insulin (prandial insulin)
 BASAL INSULINS
 Basal insulins provide a steady concentration of insulin in the bloodstream over a number of hours
 They do not act quickly
 Basal Insulin include the following intermediate and longacting insulins:
 Humulin® N (NPH)
 Novolin® N (NPH)
 Basaglar® (insulin glargine)
 Lantus® (insulin glargine)
 Levemir® (insulin detemir)
 Toujeo® (insulin glargine)
 Tresiba® (insulin degludec)
 PREMEAL INSULINS
 Premeal insulins provide a burst of insulin that acts quickly
 They are typically used 5  30 minutes before meals
 Premeal insulins include the following rapid and shortacting insulins:
 Humalog® (insulin Lispro)
 Novolog® (insulin Aspart)
 Humulin® R (Regular)
 Novolin® R (Regular)
 Insulin property chart  review of available insulins including properties, storage, etc.
 BLOOD SUGAR GOALS
Timing  Glucose goal (mg/dl) 

Fasting (no calories for 8 hours) 
75  99 
Premeal  80  120 
2 hours postmeal  < 140 
 ADA ALGORITHM FOR INITIATING INSULIN IN TYPE 2 DIABETES
 In 2015, the ADA published an algorithm for dosing insulin in Type 2 diabetes. The algorithm is summarized in the table below.
 There are a number of ways to dose insulin, and other approaches are detailed on this page
 Reference [24]
 Initial dose: 10 units/day OR 0.1  0.2 units/kg/day
 Adjust dose: increase dose by 10  15% or 2  4 units once or twice weekly to achieve fasting blood sugar goal
 If hypoglycemia occurs: decrease dose by 10  20% or 4 units
 If blood sugars are still uncontrolled after fasting target is achieved or if insulin dose is > 0.5 units/kg/day, proceed to
Step 2
 Initial dose: 4 units OR 0.1 units/kg OR 10% of basal dose
 If A1C < 8%, consider decreasing basal insulin dose by same amount
 Adjust dose: increase dose by 1  2 units or 10  15% once or twice weekly to achieve pre and postprandial goals
 If hypoglycemia occurs: decrease dose 2  4 units or 10  20%
 Initial dose: divide basal dose and give as premixed insulin twice daily (2/3 AM and 1/3 PM OR 1/2 AM and 1/2 PM)
 Adjust dose: increase dose by 1  2 units or 10  15% once or twice weekly to achieve pre and postprandial goals
 If hypoglycemia occurs: decrease dose 2  4 units or 10  20%
 If blood sugars are still uncontrolled, proceed to Step 3
 Initial dose: 4 units OR 0.1 units/kg OR 10% of basal dose before each meal
 If A1C < 8%, consider decreasing basal insulin dose by same amount
 Adjust dose: increase dose by 1  2 units or 10  15% once or twice weekly to achieve pre and postprandial goals
 If hypoglycemia occurs: decrease dose 2  4 units or 10  20%
ADA algorithm for initiating insulin in type 2 diabetes 

Step 1  start with basal insulin 
Step 2  add premeal insulin before largest meal 
Step 3  add premeal insulin before ≥ 2 meals 
 STARTING INSULIN IN TYPE 1 DIABETES (DM1)
 ADA RECOMMENDATIONS
 The ADA recommends the following for DM1 patients:
 Multidose injections (34 a day) of basal and premeal insulin, or insulin pump therapy
 Patients should match premeal insulin to carbohydrate intake, premeal blood glucose levels, and anticipated activity [10]
 GENERAL DOSING GUIDELINES
 Daily dose of insulin
 Insulin dosing in DM1 will vary based on patient's age, weight, and residual pancreatic insulin activity
 DM1 patients will typically require a total daily insulin dose of 0.4  1.0 units/kg/day
 DM1 patients may experience a "honeymoon phase" after starting insulin where lower doses are effective [7,13]
 Determining doses of basal and premeal insulin
 After the total daily dose is determined, insulin is typically administered as follows:
 Basal insulin  given as half of the total daily dose
 Premeal insulin  half of the total daily dose divided into thirds and given before each meal
 NOTE: When first starting therapy, it is recommended that the initial basal dose be reduced by 20  30% to prevent low blood sugar (hypoglycemia) [11,19]
 Example:
 Patient weighs 80kg
 Total daily dose = 80kg X (0.5 units/kg/d) = 40 units per day
 Basal insulin = 1/2 X 40 units = 20 units of basal per day*
 Premeal Insulin = 1/2 X 40 units = 20 units ÷ 3 = approximately 7 units before each meal
 * If patient is just starting therapy, the initial basal dose should be reduced by 20  30%. In our example: 20 units X 0.20 = 4 units, so initial basal dose would be 20  4 = 16 units
 STARTING INSULIN IN TYPE 2 DIABETES (DM2)
 OVERVIEW
 Insulin therapy in DM2 can range from simple onceaday doses of basal insulin to multidose regimens similar to DM1 therapy
 In DM2, insulin is often added to oral medications
 GENERAL DOSING GUIDELINES
 Basal insulin only
 Starting basal dose in DM2 patients
 Starting dose of 0.15  0.3 units/kg/day is typically safe [1,4,15]
 Starting with a flat dose of 10 units of basal insulin a day has also been shown to be safe [15]
 Typical dosing range
 Most patients will require a basal insulin dose in the range of 0.40  0.60 units/kg/day [12,13,14,15]
 Multidose regimen
 Patients already on a basal regimen can use their total daily basal insulin dose as a starting point
 Patients not on insulin can use 0.2  0.3 units/kg/day as a starting point
 After the total daily dose is determined, insulin is typically administered as follows:
 Basal insulin  given as half of the total daily dose
 Premeal insulin  half of the total daily dose divided into thirds and given before each meal
 NOTE: When first starting multidose therapy, it is recommended that the initial basal dose be reduced by 20  30% to help prevent low blood sugar (hypoglycemia) [4,11,15]
 Example:
 Patient currently uses 60 units of basal insulin a day
 Patient is switching to a multidose regimen
 Basal insulin = 1/2 X 60 units = 30 units of basal per day*
 Premeal Insulin = 1/2 X 60 units = 30 units ÷ 3 = approximately 10 units before each meal
 * If patient was just starting therapy, the initial basal dose should be reduced by 2030% In our example: 30 units X 0.20 = 6 units, so initial basal dose would be 30  6 = 24 units
 ADJUSTING BASAL INSULIN
 OVERVIEW
 There a number of ways to adjust basal insulin
 A common and straightforward method is presented here
 ADJUSTING BASAL INSULIN REGIMENS
 This method can be used for the following:
 Adjusting onceaday basal regimens in DM2
 Adjusting basal insulin in multidose (basal and premeal) regimens in DM1 and DM2
 Steps:
 1. Measure fasting blood sugar (no calories for 8 hours) for previous three consecutive days
 2. Calculate the average of the three fasting blood sugars
 3. Adjust basal insulin dose based on the table below
 4. Repeat steps 13 until target range (80  99) is achieved
Fasting blood sugar (mg/dl) average over 3 days 
Adjustment to basal insulin dose (units of insulin) 

≥ 180  add 8 units 
160  179  add 6 units 
140  159  add 4 units 
120  139  add 2 units 
100  119  add 1 unit 
80  99  no change 
60  79  subtract 2 units 
< 60  subtract 4 or more units 
 ADJUSTING PREMEAL INSULIN (SCALE METHOD)
 SCALE METHOD
 With the scale method, premeal insulin is adjusted based on a scale
 Patients should try to consume the same amount of carbohydrates at each meal (a typical amount is about 60 grams a meal and 15 grams for a bedtime snack)
 Carbohydrate goals vary by individual (see carbohydrate information below)
 Steps:
 1. Measure blood sugar fasting (prebreakfast), prelunch, predinner, and prebedtime snack for previous three consecutive days
 2. Average the prelunch, predinner and prebedtime values separately
 3. Adjust the premeal insulin dose based on the table below
 4. Repeat steps 13 until target range is achieved
 5. A Correction Factor (see below) should also be incorporated when blood sugars are checked
 If prelunch average is not in desired range, adjust prebreakfast dose
 If predinner average is not in desired range, adjust prelunch dose
 If prebedtime snack average is not in desired range, adjust predinner dose


Premeal blood sugar (mg/dl) average over 3 days 
Adjustment to premeal insulin dose 

≥ 180  add 3 units 
160  179  add 2 units 
140  159  add 2 units 
120  139  add 1 units 
100  119  maintain dose (desired range) 
80  99  subtract 1 unit 
60  79  subtract 2 units 
< 60  subtract 4 or more units 
 ADJUSTING PREMEAL INSULIN (CARBOHYDRATE COUNTING)
 CARBOHYDRATE COUNTING
 In carbohydrate counting, premeal insulin is adjusted based on the amount of carbohydrates to be consumed in each meal
 The carbohydrate counting method is used to determine the amount of carbohydrates in a meal
 An insulin to carbohydrate ratio (ex. 1 unit/10g of carb) is used to calculate the premeal insulin dose
 A typical starting ratio is 1 unit of premeal insulin for every 10 grams of carbs to be consumed
 An individual may have different carbohydrate ratios for breakfast, lunch, and dinner because a person's response to insulin may vary throughout the day
 Example:
 60 grams of carbs to be consumed for lunch
 Patient's ratio is 1 unit of insulin for every 10 grams of carbs
 Patient injects 6 units of premeal insulin before eating meal
 Steps for adjusting an insulintocarb ratio
 1. Calculate the number of carbs to be consumed in a meal using carbohydrate counting
 2. Dose premeal insulin based on number of carbs in a meal (typical starting point is 1 unit of premeal insulin for every 10 grams of carbs)
 3. Measure blood sugar fasting (prebreakfast), prelunch, predinner, and prebedtime snack for previous three consecutive days
 4. Average the prelunch, predinner and prebedtime snack blood sugar values separately
 5. Adjust the carbohydrate to insulin ratio as instructed below:
 If prelunch average is not in desired range (80  120mg/dl), adjust breakfast ratio
 If predinner average is not in desired range (80  120mg/dl), adjust lunch ratio
 If prebedtime snack average is not in desired range (80  120mg/dl), adjust dinner ratio
 If average blood sugar is > 120mg/dl, adjust ratio by subtracting 23g of carbohydrate
 Example:
 Current ratio 1 unit / 10g of carb
 Prelunch average > 120mg/dl
 Change breakfast ratio to 1 unit / 7g of carb
 If average blood sugar is < 80mg/dl, adjust ratio by adding 23g of carbohydrate
 Example:
 Current ratio 1 unit / 10g of carb
 Prebedtime snack average < 80mg/dl
 Change dinner ratio to 1 unit / 13g of carb
 If average blood sugar is 80  120mg/dl, do not adjust ratio
 6. Repeat steps 15 until appropriate ratios are determined [3,4]
 7. A Correction Factor (see below) should also be incorporated when blood sugars are checked
 ADJUSTING PREMEAL AND BASAL INSULINS CONCURRENTLY
 When adjusting premeal and basal insulins concurrently, adjustments to one regimen may affect the other regimen. This can lead to overcorrections and hypoglycemia.
 Alternating between regimens may help prevent overcorrections
 Example:
 Day 3  adjust basal
 Day 6  adjust premeal
 Day 9  adjust basal
 Day 12  adjust premeal, and so on...
 CORRECTION FACTOR
 CORRECTION FACTOR
 When blood sugar checks are high, a correction factor should be used with premeal insulin
 The correction factor supplies supplemental insulin to account for the elevated blood sugar
 Insulin used in the correction factor should not be included in calculations for adjusting premeal or basal insulin
 There are several methods that can be used to determine the correction factor
 When first starting therapy, the ideal total daily insulin dose will not be known, so the flat method is preferred over the individual method
 FLAT METHOD
 One unit of extra insulin is added for every 25mg/dl that blood sugar is above the upper limit of the desired range
 Example:
 Prelunch blood sugar is 200mg/dl
 upper limit of desired range is 120mg/dl
 200  120 = 80mg/dl above desired range
 80mg/dl ÷ 25mg/dl = approximately 3
 add 3 extra units to premeal dose
 INDIVIDUAL METHOD
 The individual method uses a patient's total daily insulin dose to calculate a correction factor
 The correction factor is calculated differently for regular insulins (Humulin R, Novolin R) and rapid insulins (Novolog, Humalog, Apidra)
 For Regular insulin (Humulin R, Novolin R)
 1. Divide 1500 by the patient's total daily dose of insulin
 2. The result will equal the estimated drop in blood sugar (in mg/dl) from 1 unit of regular insulin
 For Rapid insulin (Novolog, Humalog, Apidra)
 1. Divide 1800 by the patient's total daily dose of insulin
 2. The result will equal the estimated drop in blood sugar (in mg/dl) from 1 unit of rapid insulin [4,12]
 Example:
 Patient's total daily dose of insulin (premeal + basal) is 60 units
 Patient uses regular insulin as premeal insulin
 1500/60 = 25
 Patient can expect that for every 1 unit of regular insulin they inject, their blood sugar will come down 25 mg/dl
 Once the correction factor is calculated, the patient can then figure out how much insulin to supplement
 Example:
 Patient from above: correction factor is 25 mg/dl
 Patient checks prelunch blood sugar and it is 175 mg/dl (desired range 80  120mg/dl)
 175  120 = 55mg/dl
 55/25 = approximately 2
 Patient would add 2 extra units of regular insulin to premeal dose
 EXERCISE AND INSULIN DOSING
 See our exercise and insulin page
 SLIDING SCALE INSULIN
 Sliding Scale Insulin involves checking the blood sugar and dosing the insulin (typically rapid or shortacting) based on the blood sugar value
 Doctors use a number of different regimens depending on the patient and their sensitivity to insulin. The example below is a common starting regimen.
Blood sugar (mg/dl)  Insulin dose in units of rapid or shortacting 

< 150  0 
150  200  2 
201  250  4 
251  300  6 
301  350  8 
351  400  10 
401  450  12 
> 450  14 
 CONVERTING BETWEEN INSULIN BRANDS AND TYPES
 Overview
 It's important to note that patients may respond differently to different insulin brands and types
 The conversion guidelines presented here are meant to serve as a starting point, but they will not necessarily achieve equivalent results across all patient populations
 All patients should increase their blood sugar monitoring when switching insulins to determine the effects of the new regimen
 Converting between rapidacting (Novolog®, Humalog®, and Apidra®) and shortacting (Humulin® R and Novolin® R)
 When converting between rapidacting and shortacting insulins, the dose typically remains the same
 Rapidacting insulins act quicker (within 10  30 minutes) than shortacting insulins (within 30  60 minutes), therefore the timing of the dose should be adjusted
 Rapidacting insulins have a shorter duration of action than shortacting insulins (3  5 hours vs 6  8 hours). This may mean patients switching to rapidacting insulins from shortacting insulins may require more basal insulin to maintain blood sugar control, and vice versa.
 Conversions for inhaled insulin are discussed here  inhaled insulin dosing
 Converting between Lantus/Basaglar (Insulin glargine) and NPH
 Onceaday NPH to Lantus/Basaglar
 Dose remains the same
 Twiceaday NPH to Lantus/Basaglar
 Lantus/Basaglar dose is 80% of total daily NPH dose
 Example:
 Patient's NPH dose is 30 units twiceaday
 Total daily NPH dose is 60 units
 To convert to Lantus/Basaglar: 60 units X 0.80 = 48 units
 Daily Lantus/Basaglar dose will be 48 units [19]
 Lantus® to twiceaday NPH
 Lantus/Basaglar dose would be equivalent to about 80% of daily NPH dose
 Example:
 Patient's Lantus/Basaglar dose is 50 units a day
 To convert to NPH: 50 units = (0.80)(Daily NPH dose); Daily NPH dose = 50/0.80 = 62.5 units
 Daily NPH dose would be ∼ 62 units given in 2 divided doses
 NOTE: Patients with hypoglycemia issues may want to leave the initial daily NPH dose the same as the Lantus/Basaglar dose
 Converting between Lantus/Basaglar (Insulin glargine) and Levemir® (Insulin detemir)
 Daily dose remains the same [20]
 Converting between Lantus/Basaglar (Insulin glargine) and Toujeo® (Insulin glargine)
 Lantus/Basaglar to Toujeo
 When going from Lantus/Basaglar to Toujeo, the daily dose remains the same
 Expect that a higher daily dose of Toujeo® will be needed to maintain the same level of glycemic control as an equivalent dose of Lantus/Basaglar
 In a multidose study, the glucoselowering effect of Toujeo® was about 27% lower than that of an equivalent dose of Lantus® [21]
 Toujeo to Lantus/Basaglar
 When going from Toujeo to Lantus/Basaglar, the Lantus/Basaglar dose should be started at 80% of the Toujeo dose in order to avoid hypoglycemia
 Lantus/Basaglar is more potent than Toujeo, therefore, an equally effective Lantus/Basaglar dose will likely be lower [19,23]
 Example:
 Patient's Toujeo dose is 60 units a day
 To convert to Lantus/Basaglar: 60 units X 0.80 = 48 units
 Daily Lantus/Basaglar dose will be 48 units
 Converting between Levemir® (Insulin detemir) and NPH
 Daily dose remains the same [20]
 Converting between Toujeo® (Insulin glargine) and NPH
 Twiceaday NPH to Toujeo®
 Toujeo® dose is 80% of total daily NPH dose
 Example:
 Patient's NPH dose is 30 units twiceaday
 Total daily NPH dose is 60 units
 To convert to Toujeo: 60 units X 0.80 = 48 units
 Daily Toujeo dose will be 48 units [19]
 Converting between Toujeo® (Insulin glargine) and Levemir® (Insulin detemir)
 Daily dose remains the same [21]
 Converting between Tresiba® (insulin degludec) and all other long and intermediateacting insulins
 Daily dose remains the same
 In trials comparing Tresiba to Lantus and Levemir, the glucoselowering effect of Tresiba was equivalent to both insulins [22]
 HYPOGLYCEMIA (LOW BLOOD SUGAR)
 See hypoglycemia
 CARBOHYDRATE INFORMATION
 Carbohydrates and insulin
 It's important that diabetics who are taking insulin monitor their carbohydrate intake
 See the links below for more information on dieting and carbohydrates
 Carbohydrate counting  review of carbohydrate counting used in dosing premeal insulin
 Calories  review on calculating caloric requirements
 Diabetic diet  diabetic diet recommendations
 Carbohydrates  review of different carbohydrates found in foods
 BIBLIOGRAPHY
 What is PMID?
 PI = Manufacturer's Package Insert
 # PMID
 1  18945920
 2  PMID: 10332663
 3  PMID: 18364392
 4  Braithwaite S: Case Study: Five Steps to Freedom: Dose Titration for Type 2 Diabetes Using BasalPrandialCorrection Insulin Therapy. Clinical Diabetes Vol 23:1 p3943 2005
 5  Kulkarni K: Carbohydrate Counting: A Practical MealPlanning Option for People With Diabetes. Clinical Diabetes Vol 23:3 p120122 2005
 6  PMID: 16915796
 7  PMID: 15616254
 8  PMID: 16921608
 9  PMID: 10378067
 10  PMID: 21193625
 11  PMID: 12734137
 12  PMID: 16847295
 13  Herbst K, Hirsch I Insulin Strategies for Primary Care Providers. Clinical Diabetes. Vol 20:1 p17 2002
 14  PMID: 17890232  NEJM DM 2 study
 15  Hirsch I et al. A RealWorld Approach to Insulin Therapy in Primary Care Practice. Clinical Diabetes. Vol 23:2 p7886. 2005
 16  PMID: 18165339
 17  PMID: 12766131
 18  Glucagon PI
 19  Lantus PI
 20  Levemir PI
 21  Toujeo PI
 22  Tresiba PI
 23  Basaglar PI
 24  ADA 2015 Standards of Medical Care in Diabetes, Vol 38, Supplement 1, p. S46