The aim of the present study was to evaluate the tolerability and efficacy of the modified Atkins diet given to children and adolescents with antiepileptic drug (AED) treatment resistant epilepsy. 15 children with medically intractable epilepsy were enrolled in the study. Inclusion criteria were at least one seizure a week and a trial of at least two AEDs without obtaining seizure freedom documented in a seizure calendar. At baseline subjects initiated a diet with carbohydrates restricted to make up 10 energy percent. If seizures were reduced by less than 50% after 7-14 days carbohydrates were further restricted to 10g per day. No change in AED treatment was allowed. The diet was well tolerated. After 3 months six out of the fifteen children (40%) had a seizure reduction of more than 50%, which was seen in different epileptic syndromes and different age groups. The responders reported an increase in quality of life and cognition. At 12 months follow-up 3 (20%) continued the diet with an unchanged marked seizure reduction. The present study confirms the high tolerability and effect of the modified Atkins diet on seizure control in AED treatment resistant epilepsy. Further larger prospective studies are however needed to confirm these results.