By Dr George Samra, MB, BS (Sydney), FACNEM
The correct test for Reactive Hypoglycemia is a G.T.T. The test should be ordered by the doctor as follows: G.T.T. – 4 hours. All 1/2 hourly readings. No special diet prior.
The Glucose Tolerance Test is the classical test used in diagnosing Diabetes. The Diabetic test is a 2 hour G.T.T. with just 3 readings, the fasting, the 1 hour and the 2 hour. This test is not correct for testing Functional or Reactive Hypoglycemia. With Hypoglycemia one is interested in the full reactions to a sugar load. In both cases a 75gram load of glucose is given to the patient after having collected blood for the fasting level. With Reactive Hypoglycemia the emphasis in on the word “Reactive”- one is looking for the sugar reactive phenomenon in which the blood sugar either drops suddenly or falls very low. Part of diagnostic criteria for Hypoglycemia is the rate of fall of blood sugars, hence the relationship between consecutive readings is very important. Sudden drops in blood glucose will usually trigger an adrenaline response and subsequently adrenaline symptoms such as nervousness, shakiness, dry mouth, irritability, agitation, neck stiffness and sometimes palpitations or a racy heart.
With Reactive Hypoglycemia one is also seeking to ascertain how low the blood sugar may go as this in fact is one of the measures of severity. The brain is dependent on blood glucose as it’s only fuel supply under normal circumstances. When the blood glucose falls below a certain level, usually 3.6mm/L, there is a lack of available fuel to the brain and symptoms of brain starvation will occur – these include tiredness, moodiness, depression, forgetfulness, poor concentration and cloudy headedness.
The purpose of the G.T.T is to clarify how well one tolerates glucose and by doing it properly one is able to see if the blood sugars drop too rapidly or fall too low. It is important that the glucose tolerance test is done accurately and properly. The following rules apply:
1. Fasting for at least 10 hour prior. Usually this means fasting from 10.00p.m. the previous night.
2. Once the fasting sugar level has been collected. A 75gm glucose load is given to the patient. In children this may be adjusted according to their size, however usually a 50gm glucose load is suitable for the vast majority of children.
3. The pathology lab should be made aware that we are not trying to diagnose Diabetes but rather Reactive Functional Hypoglycemia. For this reason the doctor is requesting a longer test, i.e. 4 hours instead of 2 hours as well as all 1/2 hourly readings.
Does Insulin Need to be Measured?
Usually Insulin levels do not need to be measured. However, when the doctor suspects an Insulinoma (Cancer of the head of the Pancreas) and also in the case of an obese patient insulin levels may prove very useful in clarifying the diagnosis.
Determination of the Glucose Tolerance Test Results
The different types of Hypoglycemia have been classified based on the Glucose Tolerance Test. If the blood glucose levels falls below 3.6mm/L (65mg per 100ml) then Absolute Hypoglycemia is present. If the blood glucose level drops rapidly i.e., greater than 1.6mm/L (30mg per 100ml) in 1/2 an hour or greater than 2.6mm/L (50mg per 100ml) in 1 hour, then Relative Hypoglycemia exists. If the curve has a sharp gradient and numbers below 3.6mm/L together, then is regarded as the classical Reactive Hypoglycemia. The lower the blood sugar readings and the larger the gradient the blood glucose falls the more severe is the diagnosis. A fasting Hypoglycemia alerts the doctor the possible diagnosis of Insulinoma. The flat curve response and its implications have also been described elsewhere on this web site.
See results of a GTT and here.
What to Say to Your Doctor & How to Approach Your Doctor
Most doctors have a problem understanding Reactive Hypoglycemia and this frustrates them. For this reason I’m including a letter to the doctor that you should download and which should help you get a satisfactory response from your doctor.
HYPOGLYCEMIC HEALTH ASSOCIATION
P.O. BOX 830 KOGARAH NSW 1485
Web Site http://www.hypoglycemia.asn.au
Dear Doctor,
Your patient has identified with the many symptoms suffered by patients with Reactive or Functional Hypoglycemia. As you well know, Hypoglycemia is low blood sugar, however Reactive Hypoglycemia is a sugar reactive phenomenon (and is not Diabetes.) After a sugar load such as a soft drink or cake, patients with this condition often suffer symptoms due to a sudden drop in their blood sugars, which typically occurs between 1 1/2 hours and 2 1/2 hours after the sugar consumption. Typical symptoms of Hypoglycemia include tiredness, poor concentration, moodiness, depression, forgetfulness, nervousness and irritability.
The brain relies on glucose as its only fuel under normal circumstances. The symptoms of Hypoglycemia relate to the fact that the brain is not being fueled properly at some point in time. In order to investigate this condition and help your patient please order a Glucose Tolerance Test as follows:
GTT 4 Hours. All 1/2 Hourly Readings. No Special Diet Prior.
This is the correct way to order a test for Reactive Hypoglycemia. The patient is usually given a 75gm load of glucose soon after the fasting level has been collected. With the prolonged GTT and with the 1/2 hourly readings one is able to ascertain both the rate of fall of blood sugars as well as whether they in fact fall below the Hypoglycemia line that is usually 3.6 mm/L (65mg per 100ml). Guidelines for interpretation of the Glucose Tolerance Test are available on the web site or directly from the Hypoglycemic Health Association.
Thank you sincerely for your co-operation. This test may help to clarify many troublesome symptoms that your patient has been experiencing.
Yours sincerely,
The Hypoglycemic Health Association.
1. Wikipedia article http://en.wikipedia.org/wiki/Glucose_tolerance_test states that:
The OGTT is of limited value in the diagnosis of reactive hypoglycemia, since (1) normal levels do not preclude the diagnosis, (2) abnormal levels do not prove that the patient’s other symptoms are related to a demonstrated atypical OGTT, and (3) many people without symptoms of reactive hypoglycemia may have the late low glucoses.[citation needed]
Maybe you would like to comment on these points.
2. There are few sites out there talking about doing the GTT at home (fasting, taking 76g glucose, and testing with a glucometre)- do you think it’s a good idea?
We have found that the GTT is fairly good at diagnosing hypoglycemia (pre-diabetic diabetes)
1) Normal levels may still produce symptoms of hypoglycemia, where there is a flaw in glycolysis (ten step break down of glucose into pyruvate) called hypoglycia. Please see type 6, Hypoglycia in “What is Hypoglycemia?”
2) Translated into English this question seems to mean: “abnormal GTT do not prove that the patient’s other symptoms are related to a demonstrated abnormal GTT”.
This may be true, because apart from or in addition to hypoglycemia the patient could also suffer from an array of other metabolic disorders, such as heavy metal intoxication or hypothyroidism, or “leaky gut syndrome”. See “Silent Diseases and Mood disorders“.
3) This question is somewhat obscure, but it may may mean that a person could could be shown to have hypoglycemia in a longer than normal GTT. The question can also mean that a person may have hypoglycemia and show no symptoms normally associated with hypoglycemia; such as perhaps “anger management problems” or “perfectionism” or “irritability” etc etc.
4) The last question is about an alternative to doing a home GTT by completing the NBI test, or “Hypoglycemia Questionnaire”. But many people are using the test with a Glucometer at home. If you do so you can compare the results with the six types of hypoglycemia as explained in the article “What is Hypoglycemia?”
Nevertheless, a GTT is best performed under controlled conditions in a laboratory by a nutritional doctor.
An important principle in nutritional therapy is to FIRST eliminate any possible biochemical abnormality by pathology tests that can be responsible for sympytoms, BEFORE considering “psychological” factors.
I hope this answers the question.
Jurriaan Plesman
I have had symptoms of shaky hands tact heart chest pains and there are times when I don’t eat regularly I feel different hard to explain it thenwhen I’m walking the room around me feels like a mirror room from a carnival and then I can’t talk I basically mumble so low and I’m not myself like I’m a different person when U see food I’m shoving everything in my mouth like I haven’t ate for days
Hi Heather, It is difficult to understand what your symptoms are. I suggest you adopt the hypoglycemic diet and if things don’t improve please consult a nutritional doctor.
Not many people are successful in testing themselves properly for hypoglycemia. We have several paper-and-pencil questionnaires that are just as reliable. They can be found at:
Nutrition-Behavior Inventory (NBI)
http://www.hypoglycemia.asn.au/2011/testing-for-hypoglycemia-and-how-your-doctor-can-help/
Hypoquiz
http://hypoglycemia.org/quiz
Hypoglycemic Questionnaire (short test)
http://curezone.com/upload/PDF/Articles/jurplesman/HYPOGLYCEMIA_QUESTIONNAIRE.pdf
When testing with a Glucometer at home, you must follow strictly the instructions by Dr George Samra. If you want to interpret the result of your readings from a glucometer – half-hourly readings over four hours total – you can compare the results with that shown shown in
What is Hypoglycemia?
http://www.hypoglycemia.asn.au/2011/what-is-hypoglycemia/
There are six types of hypoglycemia. Please note Type 6.
I wake up at 2:00 am every day, sweaty. I get a panicky feeling in the pit of my stomach and need to make a bowel movement quickly, sometimes two or three Bowel movements. I get palpitations and sometimes I can fall asleep again, but more often that’s the end of sleep for me. I always have a whole wheat bread with some peanut butter before bed. I believe I’m having hypoglycemia at night, but doctors measure my glucose (95) and conclude I’m not hypoglycemic. I’m desperate to find a solution because I look awful and feel awful when I don’t get any sleep. I’m barely functioning. I feel better by mid- afternoon, only to start the cycle all over again. Any help you can provide?
Debra
Always be careful, when doctors say you are not hypoglycemic. Usually they are not aware how to test for hypoglycemia as distinct from diabetes.
See:
Testing for Hypoglycemia,
http://www.hypoglycemia.asn.au/2012/self-help-website-for-personal-growth/#Testing
You can also test yourself at home by
Testing for Hypoglycemia by Questionnaires
Nutrition-Behavior Inventory (NBI)
http://www.hypoglycemia.asn.au/2011/the-nutrition-behaviour-inventory-nbi/
Hypoglycemic Questionnaire (short test)
http://www.hypoglycemia.asn.au/2012/hypoglycemia-questionnaire/
If you score high it may be an indication that by ou are hypoglycemic.
Usually people that wake up at night are found to be hypoglycemic. Look up the use of GLYCERINE in “Research for Hypoglycemia”
I have been sick for 8 months I have lost an unintended 71 lbs ( which I struggled the last 5years loosing due to PCOS) I have nausea, lack of apetite, fatigue, neck stiffness and pain, back pain, joint pain, shakiness, severe itchy skin use to be only at night now it’s all day, cold hands and feet, reaccurent sinus infections, and the most confusing issues with my blood sugar. As far as my blood sugar I noticed In may I felt terrible bouts of these alternating symptoms only to find out I was expieriencing low blood sugar. My doctors took me off of metformin ( I took for 2 years for PCOS) and I had blood sugars in the 400′s and as low as 37. They freaked out and put me on Januvia even though I am NOT diabetic. I have in the last 5 months been to multiple specialists and had a million tests, procedures, surgerys looking for what’s killing me! they have found abnormalities but not to degrees to explain what is causing this! As of September I have developed anemia of chronic disease( low transferrin borderline low iron stores) my hair is falling out (gross) I bruise easily and get rashes of petechia I recently came off my januvia for another OGGT my fasting blood sugars are most comfortable to me symptomaticly, my dating blood glucose after was 84 my 30 minutes blood sugar (after 75mg sugar drink) was 110. 30 minutes later it was 77 and thirty minutes later it 74 and 30 min later it was 70. It was not long enough and now I’ll be doing a five hour on Monday- they tested my insulin at each 30 min and my c peptide both were low insulin very low c peptide moderately low. I am lucky I have good doctors desperately looking for answers but I am scared it will be too late. Next week I’ll be having a bone marrow biopsy and a scalp biopsy even though they are not sure what could cause the spontaneous reactive hypoglycemia- I have 3 small children with a chronic disease who I need to be around to take care of and a husband who loves me. With little minor health issues before. I am a 30yr old female. I am looking for ideas or and direction anyone has??
My goodness, you have a lot of problems. I am glad to hear you are in the hands of good doctors. Also try to get some advice from nutritional doctors. No doubt the hypoglycemic diet will help you but be aware of allergies. Read some articles on allergies at our web site. I hope you will recover.
i found out myself hypoglycemic only last week and started following a diet plan. i got a severe migraine, one such i never hve had in my life time, and i think that was a withdrawal symptom. Actually i don’t have a sugar addiction or coffee addiction, actually i dont take coffee at all. still i eat cookies and biscuits. of late i get a strange feeling in my brain, a kind of something spreading from one side to the other.. is it some nerve disorder or rather lack of glucose.it continues after the diet plan also. im confused, any reply…pls
I might be an idea to try out the hypoglycemic diet, including avoidance of allergies (See Dr George Samra’s books and articles in our web site). If after three week the symptoms persist I strongly advise to see a nutritional doctor. Cheers Jur.
I have been suffering from migraine for 25 yrs and mild but chronic hypoglycaemic problems.
In the last four years I have suffered from crushing insomnia waking up every 2-3 hrs through the night with heart palpitations and I am assuming elevated adrenalin levels after these episodes as I’m awake for 2-3 hrs afterwards.
Could this all be related to hypoglycaemic episodes?
Yes you insomnia could be related to hypoglycemia. Also read:
Yes youR insomnia could be related to hypoglycemia. Also read:
Biochemistry of Insomnia
http://www.hypoglycemia.asn.au/2011/the-biochemistry-of-insomnia/