Antimicrobial-associated encephalopathy due to ampicillin.

Because the β-lactam ring has a molecular structure similar to that of gamma-aminobutyric acid (GABA) neurotransmitters, it binds to GABA A receptors and inhibits GABAergic transmission, causing AAE. The possibility of antimicrobial-associated encephalopathy should be considered in cases of neurological or psychiatric symptoms after initiating an antimicrobial regimen.