Provided herein are compositions, combinations, and methods comprising NMDA antagonists including, but not limited to, NMDA glutamate receptor antagonists such as [2-(8,9-dioxo-2,6-diazabicyclo[5.2.0]non-1-(7)-en-2-yl)alkyl]phosphonic acid and derivatives thereof, which are effective in reducing the amount of anesthetic required to maintain anesthesia (i.e. to achieve an anesthetic-sparing effect).
NMDA ANTAGONIST FOR ACHIEVING AN ANAESTHETIC-SPARING EFFECT