The present invention demonstrates the therapeutic use of ketone esters for seizure disorders, Alzheimer's disease malignant brain cancer, and other cancers, which are associated with metabolic dysregulation. The administration of a ketogenic diet, such as ketone esters, while concurrently subjecting the patient to a hyperbaric, oxygen-enriched environment resulted in therapeutic ketosis. Optionally, the hyperbaric, oxygen-enriched environment is 100% oxygen at 2.5 ATA absolute. The ketone esters may be derived from acetoacetate and can include R,S-1,3-butanediol acetoacetate monoester, R,S-1,3-butanediol acetoacetate diester, or a combination of the two. The treatment may further include administering at least 10% ketone supplementation, such as acetoacetate, adenosine monophosphate kinase, 1,3-butanediol, or ketone ester, to the patient.