If a child is taking high dosages of several antiepileptic drugs, tapering of one drug is started around the time the diet is started. If ketosis is maintained and seizure control improves, a further reduction in medications is often possible. Occasionally, all medications can be tapered and stopped.
After one-year of therapy, approximately one third of patients experience a greater than 50% reduction in seizures (10% are seizure-free), one-third have less than a 50% reduction, and one-third are unable to tolerate the diet.
The long-term effects of a high-fat diet, even if it is used for only several years, are unknown. Most experts believe benefits for brain development and intellectual and social functions with improved seizure control and reduced dosages of antiepileptic drugs outweigh the risks. Many parents worry about the potential effects of large amounts of dietary fat. Although the ketogenic diet raises "bad" lipids (VLDL and LDL) and lowers "good" lipids (HDL), there is no evidence of increased atherosclerosis in children or adolescents. Weight gain is not usually a problem on this diet because caloric intake is carefully supervised.
The initial starvation (if used) can cause very low blood sugar levels that require urgent treatment. Other potential problems include a deficiency of the vitamins B, C, and D; calcium, folate, and iron. These nutrients must be supplemented. The ketogenic diet often slows a child’s growth in height and weight, but this is often made up for, at least partially, when the diet is stopped. There is also a risk of kidney stones, but the risk is reduced by adequate fluid intake. Although acetazolamide, topiramate, and zonisamide can predispose to kidney stones, they can still be used by patients on the diet. Other complications include constipation and an increased risk of bone fractures.
The Ketogenic Diet: A Treatment for Epilepsy, 3rd Edition
by John M. Freeman, Jennifer B. Freeman, Millicent T. Kelly
The Ketogenic Cookbook
by Dennis Brake, Cynthia Brake