As the ketogenic diet uses lipids rather than carbohydrates as the primary energy source, it is essential that children are screened for disorders of fat metabolism, fatty acid transportation and oxidation, to avoid metabolic crisis.1  

The absolute and relative contraindications and other pre-existing complications are listed below.

Absolute contraindications:

  • Carnitine deficiency (primary)
  • Carnitine palmitoyltransferase (CPT  I or II) deficiency
  • Carnitine translocase deficiency
  • b-oxidation defects
  • Medium-chain acyl dehydrogenase deficiency (MCAD)
  • Long-chain acyl dehydrogenase deficiency (LCAD)
  • Short-chain acyl dehydrogenase deficiency (SCAD)
  • Long-chain 3-hydroxyacyl-CoA deficiency
  • Medium-chain 3-hydroxyacyl-CoA deficiency.
  • Pyruvate carboxylase deficiency
  • Porphyria

Most of these conditions can be excluded on a routine urine metabolic screen and blood carnitine profile.

Relative contraindications:

  • Inability to maintain adequate nutrition
  • Surgical focus identified by neuroimaging and video EEG monitoring
  • Parent or caregiver hesitance re: fussy eaters, diet and noncompliance with diet
  • Bulbar dysfunction or Gastroesophageal disease -> aspiration risk
  • Fat micro-aspiration – fat aspiration pneumonia -> severe complications

Most patients will require a risk assessment of aspiration as fat-aspiration can be lethal.

Other pre-existing complicating factors to be considered:

  • Presence of kidney stones
  • Dyslipidaemia
  • Liver disease
  • Failure to thrive
  • Gastroesophageal reflux
  • Poor oral intake
  • Constipation
  • Cardiomyopathy
  • Chronic metabolic acidosis
  • High carbohydrate content of current medications
  • 1. Kossof et al. (2009). Optimal Clinical management of children receiving the ketogenic diet: Recommendations of the international Ketogenic Diet Study Group. Epilepsia, 50(2):1-14.