Disclosed herein are isotopically enriched compounds and methods of using both isotopically and non-isotopically enriched compounds of the following formula

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in the treatment of neurologic and brain disorders/conditions.

Disclosed herein are isotopically enriched compounds of the formula

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including enantiomers and mixtures thereof, as well as methods for their use and the use of MDE in treating neurologic and brain disorders.

Ketamine derivatives and pharmaceutical compositions thereof are disclosed. When administered orally the ketamine derivatives provide increased bioavailability of ketamine in the systemic circulation. The ketamine derivatives can be used to treat neurological diseases, psychological diseases and pain.

Ketamine derivatives and pharmaceutical compositions thereof are disclosed. When administered orally the ketamine derivatives provide increased bioavailability of ketamine in the systemic circulation. The ketamine derivatives can be used to treat neurological diseases, psychological diseases and pain.

Ketamine derivatives and pharmaceutical compositions thereof are disclosed. When administered orally the ketamine derivatives provide increased bioavailability of ketamine in the systemic circulation. The ketamine derivatives can be used to treat neurological diseases, psychological diseases and pain.

Ketamine derivatives and pharmaceutical compositions thereof are disclosed. When administered orally the ketamine derivatives provide increased bioavailability of ketamine in the systemic circulation. The ketamine derivatives can be used to treat neurological diseases, psychological diseases and pain.

Ketamine derivatives and pharmaceutical compositions thereof are disclosed. When administered orally the ketamine derivatives provide increased bioavailability of ketamine in the systemic circulation. The ketamine derivatives can be used to treat neurological diseases, psychological diseases and pain.

Ketamine derivatives and pharmaceutical compositions thereof are disclosed. When administered orally the ketamine derivatives provide increased bioavailability of ketamine in the systemic circulation. The ketamine derivatives can be used to treat neurological diseases, psychological diseases and pain.

Ketamine derivatives and pharmaceutical compositions thereof are disclosed. When administered orally the ketamine derivatives provide increased bioavailability of ketamine in the systemic circulation. The ketamine derivatives can be used to treat neurological diseases, psychological diseases and pain.

The invention provides a lactate dehydrogenase inhibitor that makes it possible to suppress refractory epilepsy in which conventional antiepileptic drugs are ineffective, and an antiepileptic drug containing said inhibitor. The lactate dehydrogenase inhibitor of the invention contains a compound represented by formula (III); i.e., isosafrole or a compound having isosafrole as a scaffold, and the antiepileptic drug of the invention has these compounds as an active ingredient. ##STR00001##