By disrupting a natural process used by developing mammalian brains to prune and delete surplus neurons, surgical anesthetics and other drugs that suppress brain activity in fetuses and infants can trigger permanent pathological brain damage. That type of damage can be prevented by drug interventions that block one or more "upstream" events that otherwise would lead to the release of "Cytochrome C", a messenger molecule that triggers apoptosis (programmed cell death) among immature neurons. Lithium is a potent protective agent that can be coadministered along with ketamine or other NMDA-acting or GABA-acting anesthetics and anticonvulsants. Xenon gas triggers only mild damage, and can enable improved anesthesia when combined with other drugs. Other protective drugs (also called safener drugs), and treatments that can prevent or minimize fetal alcohol syndrome, also are disclosed.