The ketogenic diet should be considered as alternative therapy for children with difficult-to-control seizures. It is more effective than many of the new anticonvulsant medications and is well tolerated by children and families when it is effective.

HE KETOGENIC DIET IS A HIGHfat low-carbohydrate adequate protein diet first developed 8 decades ago for the management of difficult-to-control seizures in children. 1 Recent studies have documented the short-term and longterm benefits of this diet in improving seizure control. 2-4 An evaluation by the Blue Cross/Blue Shield Technology Center reported 5 ". .. the diet's effectiveness in providing seizure control for children with difficult-to-control seizures has remained as good, or better than any of the newer medications." Although the mechanisms by which the diet decreases seizures remain unknown, 6,7 the level of ketosis produced by the incomplete oxidation of fats when carbohydrates are in short supply appears to play a critical role in the effectiveness of this diet. 1 The classic ketogenic diet consists of a 4:1 ratio of fat to carbohydrate and protein combined. 3 Because there are 9 calories/g of fat compared with 4 calories/g of either carbohydrate or protein, the fat content of such a ketogenic diet provides 90% of the child's calorie intake. Carbohydrates are severely restricted and are usually less than 10 g/d. Younger rapidly growing children and adolescents are often started in treatment by receiving a less stringent 3:1 ratio of fat to carbohydrate plus protein to allow sufficient protein (1-1.5 g/kg per day) for growth. Growth while receiving the ketogenic diet remains within the normal range. 8

Hemidecortication continues to be a beneficial procedure in reducing seizure frequency in cases of unilateral cortical epilepsy. Fewer children with migrational disorders are seizure-free.

The ketogenic diet is a safe, well-tolerated, and possibly effective potential alternative to other therapies for infantile spasms.

The objective of this study was to determine the relationship between β-hydroxybutyrate levels and seizure control in children on the ketogenic diet. Seventy-four children on the ketogenic diet presenting for routine follow-up visits had blood levels of β-hydroxybutyrate correlated with their seizure control. Forty-two children admitted for initiation of the ketogenic diet had urine ketones measured by dipstick and correlated with simultaneous blood levels of β-hydroxybutyrate. Blood β-hydroxybutyrate levels statistically correlated with seizure control (P = .003). Children with blood β-hydroxybutyrate levels greater than 4 mmol/L were significantly more likely to have a decrease in seizure frequency than those with levels less than 4 mmol/L. Urine ketones of 4+ (160 mmol/L) were found on dipstick when blood β-hydroxybutyrate levels exceeded 2 mmol/L. Seizure control correlates with blood β-hydroxybutyrate levels and is more likely when blood β-hydroxybutyrate levels are greater than 4 mmol/L. The traditional measurement of urine ketones by dipsticks in children on the ketogenic diet provides a less than optimal assessment of the degree of blood ketosis. Three to four plus (80-160 mmol/L) urine ketones are necessary, but not necessarily sufficient, to achieve optimal seizure control in children on the ketogenic diet. At present, however, urine ketones are the only readily available inexpensive approach to ketone assessment. (J Child Neurol 2000; 15:787-790).