Ketogenic diet in epilepsy: an updated review

SUMMARY Introduction. Finding an effective epilepsy treatment has been a challenge in medicine for centuries. It is especially difficult to treat drug-resistant epilepsy, which accounts for 20–30% of epilepsy cases, even after the introduction of numerous new anti-epileptic drugs (AEDs). This gives an incentive to search for therapies other than pharmacotherapy, e.g. the ketogenic diet (KD). Aim. The present review paper aims to present the current state of knowledge regarding the effectiveness of the KD, its mechanism of action, indications, method of treatment and potential adverse effects. Material and method. The review covers relevant most recent (up to March 2018) papers using PubMed and Medline databases. Results and discussion. The history of the KD dates back to ancient times. It was believed to be very promising at the beginning of the last century, but then was temporarily ‘forgotten’ and has been undergoing a second renaissance since around 1990. It is currently recognised in most countries. The KD is administered mainly to children but over the last few years there have been attempts to use it in adults as well. The theoretical basis of the diet consists in the fact that it ‘mimics’ the metabolic state of an organism subject to fasting by replacing the basic source of energy for the brain, that is glucose, with ketone bodies, which are a product of fat breakdown. In spite of scientific progress, the exact mechanism underlying the KD is still not known. Its effectiveness, at first mainly as an add-on therapy, and in some cases as the first-line monotherapy, is rated quite highly (<50% seizure reduction in <50% patients; of which in 20–30% of patients seizures are reduced by <90%). It can be used to treat all types of epileptic seizures after excluding contraindications. The KD, like any medical therapy for serious illnesses, may cause adverse effects. Most of them are mild, can be prevented, and if they occur, can be fairly easily treated Conclusion. The KD as add-on therapy or as monotherapy is a medical treatment of epilepsy administered under medical supervision.