Ketogenic Diet and Seizures

Ketogenic Diet and Pediatric Seizures

During this holiday season many people are looking for the perfect diet to help them balance out all of the high caloric intake. What could be more perfect than trying to loose your excess holiday weight by reigning yourself in and confining your diet to Bacon and Eggs?  Hmmm… Bacon!

While I may love Bacon, trying to sustain a ketogenic diet is difficult (eventually the craving for bread becomes too much for me personally), but what about those children with seizure disorders who are also placed on ketogenic diets to help control their seizures? Is asking about diet history really that important to me in the ED?

Ketogenic Diets and Pediatric Seizure Disorders

You may have encountered a patient who is on a ketogenic diet to help control his/her seizures.  Most often this is in a child who has difficult to control seizures despite antiepileptic medications.  Many times the child will have several other significant medical conditions.  Ketogenic diets have been used for decades to help control seizures.  Recently a Cochrane review looked at several quality studies on the topic and stated:

These studies suggest that in children, the ketogenic diet results in short to medium term benefits in seizure control, the effects of which are comparable to modern antiepileptic drugs. …  However, all studies showed 30-40% reduction in seizures compared to comparative controls.

So, if changing a diet can be as helpful as taking a medication, why don’t more patients use it?  Well… it is likely the same reason I cannot adhere to the diet either.  But, there are also some medical complications that we need to consider when we evaluate patients on ketogenic diets.

Potential Complications of Ketogenic Diets

  • Early Complications (<4 weeks after starting diet)
    • Dehydration was the most common complication
    • Hypoglycemia
      • This can even be severe and life-threatening in a child with an inborn error of metabolism.
      • Underlying metabolic disorders need to be carefully screened for prior to starting the diet.
      • Transient hypoglycemia can be commonly seen after the diet is initially started; however, most remain asymptomatic and self correct with increase in caloric intake
    • GI disturbance
      • Diarrhea or Constipation
      • Nausea and Vomiting
      • Exacerbation of Gastroesophageal Reflux (high fat content delays gastric emptying)
    • Acute pancreatitis
      • Rare but serious (often fatal)
      • Likely attributable to Hypertriglyceridemia
    • Infectious Disease
      • No clear mechanism for increased risk of serious bacterial infections.
      • Impaired neutrophil function has been shown in vitro.
    • Hyperuricemia
    • Persistent Acidosis
    • Hypomagnesemia
    • Hypercholesterolemia and Hypertriglyceridemia
  • Late Complications (> 4 weeks)
    • Osteopenia
    • Kidney Stones
    • Cadiomyopathy
      • Rare by can be fatal
      • Bradycardia, diminished QRS voltage, and prolonged QTc have been seen.


Most often these complications will improve with conservative management.  The child who is on a ketogenic diet usually is followed closely by the team of neurologists as well as dieticians who will be monitoring for these potential complications, but it may be you who picks up on the symptoms so, as always, be vigilant.

What should you do, though, when the child presents with a Seizure?

Considerations with Child Presenting with Sz

  • Manage the seizure as you would normally (ie, Benzos, Phenytoin/Keppra, etc).
  • Consider all of the above potential complications as reasons for the child’s seizure threshold to have been lowered.
    • Certainly, being dehydrated may exacerbate their seizure disorder.
    • May want a lower threshold for screening for serious bacterial infections.
  • If you find the child to be hypoglycemic, remember that giving glucose may actually lead to increased seizure activity.
    • No guidelines on this… but if the glucose level is significantly low, treat it (you will likely be treating additionally seizure activity either way).
    • If the child has stopped seizing and you find the glucose level to be borderline low, the child may benefit more from close monitoring.
  • If you like to use Propofol for patients that you have had to intubate for status epilepticus, realize that patient’s on ketogenic diets may be more predisposed to Propofol-Infusion Syndrome.
Levy RG, Cooper PN, Giri P. Ketogenic diet and other dietary treatments for epilepsy. Cochrane Database Syst Rev, 2012
Sharieff GQ, Hendry PL. Afebrile Pediatric Seizures. Emerg Med Clin N Am. 2011: 29; 95-108.
Hoon Chul Kang, Da Eun Chung, Dong Wook Kim, Heung Dong Kim. Early- and Late-onset Complications of the Ketogenic Diet for Intractable Epilepsy. Epilepsia. Sept 2004: 45(9); 1116-1123.


Sean M. Fox
Sean M. Fox

I enjoy taking care of patients and I finding it endlessly rewarding to help train others to do the same. I trained at the Combined Emergency Medicine and Pediatrics residency program at University of Maryland, where I had the tremendous fortune of learning from world renowned educators and clinicians. Now I have the unbelievable honor of working with an unbelievably gifted group of practitioners at Carolinas Medical Center. I strive every day to inspire my residents as much as they inspire me.

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