Friday, January 25, 2013

Tips for testing before meal and bedtime glucose levels

                                        Question answers from yesterday
 Common ways of increasing Basal insulin and correcting the fasting glucose include.

  #1  adjusting the basal rate on a persons insulin pump      yes      
  #2  adjusting the dose of Lantus insulin                                yes     
  #3  adjusting the dose of bedtime NPH insulin                     yes      
  #4  adjusting the dose of oral diabetes medication              yes      
  #5  adding a medication  to more effectively  control 
        glucagon levels                                                                    yes     
  #6  checking a 3 am glucose                                                     no
  # 7 not eating a bedtime snack                                                 no

We have spent a lot of time discussing the importance of checking the fasting blood glucose and looking for patterns. 

Review and suggestions
Persistent  elevation of the fasting blood glucose suggest that you are not producing or taking enough insulin to maintain normal glucose and fat metabolism and it is time to talk to your health care provider about medication adjustments.

Occasional elevation is often unexplained but can be caused by an unrecognized low blood sugar at 2 to 3 am. It is time to  start checking  bedtime and 3 am glucose levels.

Occasional low fasting glucose can be a warning of a severe hypoglycemia in the future.  It is definitely time to start checking bedtime and 3 am glucose levels and talk to your health care provider about medication adjustments.

Testing before meal and bedtime glucose levels

Starting the previous meal with a elevated glucose almost guarantees an elevated glucose before the next meal

People taking
 Oral diabetes medications or injectables , such as Byetta or Victoza
     (assuming you started the previous meal with with your glucose on target)
These test are useful for helping you determine if you are producing or taking enough insulin to allow you to use or store the glucose from the carbohydrate eaten with the previous meal. 

People taking 
a rapid acting insulin before each meal or snack  have a little advantage. They have probable been trained to use *formulas that will allow them to take extra insulin to correct the elevated glucose and then also adjust the insulin dose to take enough insulin to efficiently use the glucose from meal.

* correction factors for Aperson
    1 unit of insulin will reduce the glucose x amount 
     For example .  Aperson has worked with their health care provider( usually a dietition / diabetes
                             educator) and  determined that 1 unit of rapid acting insulin will lower an elevated
                             glucose level by 20 mg/d
                             glucose goal before lunch is 90 to 120 mg/dl
                             test result 160 mg/dl
                             Take 1 unit of insulin for each 20 mg /dl above goal = 2 units

        #2Insulin / carbohydrate ratio
     For example. Aperson has worked  with their health care provider and determined that  1 unit of
                           rapid acting insulin will allow them to efficiently metabolize 30 grams of carbohydrate.
                           Carbohydrates eaten 90 gms
                           90 divided by 30 = 3 units of insulin
                          Aperson's total insulin dose   5 units 

        Track 3 is a good iphone app to help with these calculation

Have Fun , Be Smart and check your blood glucose levels wisely
David Calder,MD


  1. so what time is considered "bedtime" example, 10.00 pm level is 139,at 1200 its 88 my actual usual bedtime.

    1. Thanks for your comment .
      Your bedtime glucose is determined by the time from and amount of your last meal , snacks and your diabetes medication. Your 1200 hour glucose of 88 suggest that you will be lower at 2 to 3 am and at risk of hypoglycemia. This is a time of day when we are all the most sensitive to the effects of insulin .I think it would be wise to check a few 3 am glucose test and consider a " bed time snack ". You may need to adjust your diabetes medication and/or your diet.
      Dr. Calder

  2. Hi Dr. Calder,
    There is a product called 4amglucose (I saw it on AADE13). If Betty take it at 10 pm bedtime, it releases glucose around 12 to 5 am. Would you think it help Betty's situation?

    1. Good idea.people taking insulin and some oral diabetes medications ( sulfonylureas) are at the greatest risk of low glucose levels between 2and 3 am. The idea of having a bedtime snack has been around for many years. A typical bedtime snack is 30 grams of carbohydrate( 1 cup of skim milk and a slice of whole wheat bread ) . Each 4amglucose tablet has 3 gms. of glucose. How many tablets would a person need to take to to match the usual bedtime snack ?
      The cost is 19 $ /bottle. Think about it. Dr. Calder

    2. However, Dr. Calder, we may have to consider the efficiency here.
      When we eat any food, it has to be absorbed and digested by GI tract, and the blood glucose level may shoot up early causing hyperglycemia and weight gain (as seen on Glucerna website). By 3 to 4 am the glucose may depleted and not as effective at all. While this product, according to the website USP dissolution profile, delivers glucose after 2 hours of being taken, and release all sugars by 7 hours. It certainly sounds very efficient and clever. We may not need so many tabs for the effects. Is that sounds right Dr.?

  3. Dr. Calder, please unswer my posting last week. Give your intelegent and professional thoughts, would you?


Your comments and questions are appreciated. David Calder,MD