Seizures in the setting of hypoglycemia are well described. The brain needs sugar to function and when the blood sugar falls “too low”, one of the things that can happen is that the patient may have a seizure (this is usually a generalized convulsion-a tonic-clonic or Grand Mal seizure). There is no one level of blood sugar below which one has a seizure (rather the level varies from person to person). Let me explain that with an example. Lets assume you are a diabetic and you take your insulin shot but for once forget to take a meal (maybe you are a hard working executive on the run). You have a convulsion while at work and are taken to the nearest ER. There your blood sugar at the time of presentation is recorded to be 60 mg/dl. There might be another similar patient whose blood sugar falls to 52mg/dl yet he does not have a convulsion. So there is no set limit below which the brain shall have a seizure but speaking in broader terms usually the brain does not tolerate blood sugar below 60mg/dl and below 40 mg/dl most patients shall be symptomatic (either have a convulsion or be confused and obtunded. The term used for this constellation of neurological signs and symptoms as a result of hypoglycemia is NEUROHYPOGLYCEMIA).
The good news though is that seizures due to hypoglycemia are readily treatable. In the ER we load the patient with glucose (usually this is given via an intravenous drip as the patient is obtunded and confused and cannot accept anything from the mouth). The blood sugar quickly rises and the seizures stop. Patients who suffer from hypoglycemic seizures do not need to be on an anti-epileptic drug. These patients do not have epilepsy. If their blood sugar does not fall down again, they will not have another seizure.
Rather a meticulous search should be conducted to find out the cause of hypoglycemia:
-is the patient a diabetic who took too much insulin by mistake?
-did he miss his meal but took his insulin?
-is there any other cause of hypoglycemia such an insulin secreting tumor?
-is the patient septic?
Hypoglycemic seizures are most commonly seen in diabetics. This emphasizes the importance of good glycemic control in this vulnerable population.
Nitin Sethi, MD
Filed under: Uncategorized | 9 Comments
Tags: convulsion, epilepsy, hypoglycemia, low blood sugar, seizures, treatment
Search
-
You are currently browsing the Braindisease's Weblog weblog archives.
Hi,
May I ask the folowing question. I Have type I diabetes and have found that when my blood sugar is running a little low, I can becme photosesntive- experiecing mild ’shocks’ or seizures throughout my body when exposed to flickering lights. Can these two events be correlated in any way?
Thank-you for your time.
Tim
Dear Tim,
what is most likely happening is that you are experiencing systemic signs and symptoms of hypoglycemia. These include feeling nervous, agitated, irritable,tremulous (feeling minor tremors in the body)and palpitations.
Seizures with hypoglycemia are not common and they only occur when your blood sugar falls real low.
Personal Regards,
Nitin Sethi, MD
Dr Sethi,
I am very interested in this subject. My 16 yr old daughter is a long time kidney /transplant patient with every complication under the sun. She has had two sets of nephrectomies, maiden and graft, PTLD cancer in the liver, battled diabetes last year, recent encephalitis, and is currently on hemodialysis again waiting for her second kidney transplant.
My daughter’s dialysis unit has recently instituted a policy restricting food and drink during treatment and this is beginning to exasperate her headaches, nausea, and blood sugar swings while on dialysis. Although not currently diabetic, we have been monitoring her blood sugar levels throughout her treatments because she has had one seizure and two that were averted with fluid returns. Her bg’s were as low as 60 with the seizure, but the other two times I noticed it wasn’t the actual blood sugar level, but the fact that she dropped 20-25 points in a 15-30 minute time frame. Is this because of her not eating? Is that safe? Could that be causing undo harm to her neurologically or bringing back the diabetes?
Thank you for you help!
Liz
Dear Liz,
you do raise a very valid point. You are right, it is not the absolute number to which the blood sugar drops to, but the rate of fall which at times determines if a patient becomes symptomatic because of hypoglycemia (low blood sugar). The same holds true for other electrolytes like sodium. Let me explain with the aid of an example. A person is more likely to be symptomatic if his/her blood sugar drops acutely (rapidly) from 120 to 70, rather than one whose blood sugar drops from 120 to lets say 60 over a period of time. This is because a slower fall gives the body and the brain time to get adjusted to the low sugar and draw on other reserves.
Your daughter likely has a very brittle control of her blood sugar, this is because during dialysis there are rapid shifts in the body’s fluid and electrolytes (sodium, potassium, calcium). Neurohypoglyemia can prove to be dangerous-as I stated in my post, patients can have seizures if the blood sugar falls down too low.
She should have close blood sugar monitoring and an attempt made to avoid rapid and wide fluctuations in the blood sugar levels.
Personal Regards,
Nitin Sethi, MD
Dr Sethi,
How would your experience suggest the attempt at preventing the wide/rapid fluctuations in blood sugar levels?
Do you reccomend the withholding of nuttrition and fluid during dialysis treatment?
Thanks,
Liz
Hmm Liz, that is indeed a tough one to answer. Fluid and electrolyte balance is a delicate one and sometimes needs very fine tuning–you do not want fluid overload or increased electrolytes (blood sugar included) as well as fluid depletion and low electrolytes (hyponatremia, hypoglycemia etc). Usually the nephrologists are the best to manage this.
Personal Regards,
Nitin Sethi, MD
Hi,
I seem to be having a problem with my blood sugar. Sometimes for no particular reason my body starts to shake, i get confused and disoriented. It feels like I am going to lose consciousness. It takes a great deal of sugar to bring me back to normal. i eat sugar on a daily basis, because when I stop this issue seems to occur. If I stop eating the sugar on a daily basis, it seems to occur more offten. Any idea what is going on or where to look for answers. I get sent for a blood test and nothing shows up. My younger brother does have type 1 diabetis. I have been tested for diabetis all my life and comes back negative, however I continue to struggle with diving blood sugar issues, and it can be very scary. Any idea what is going on?
thanks
Liza
My best friend had been battling hypoglycemia for the last 10 years. She had her first grand mal seizure 10 years ago it was then found that her blood sugar was 39. She frequently monitors her blood sugars levels and carries juice with her all of the time. She recently began having seizures (grand mal) on a regular basis in the early morning hours despite waking frequently throughout the night to have a snack of peanut butter and crackers. Her blood sugar levels run on average in the 40’s, it is very rare that she can go over 60 and if she gets that high it will not remain for longer than 30 minutes at a time. She has had many tests and was even told by a specialist that this was all in her head and was prescribed an anti anxiety medication. She always feels tired and lethargic. Her Dr.s have inquired about alcoholism and she does not consume any alcohol at all as she fears for her life. What is the next step?
Dear April,
thank you for writing in. I am not sure what plagues your friend. The best approach shall of course be to first determine what is the cause of her recurrent bouts of hypoglycemia and secondly are her seizures related to hypoglycemic attacks.
If she indeed has seizures due to hypoglycemia, the treatment shall involve correcting the underlying etiology of hypoglycemia.
Personal Regards,
Nitin Sethi, MD