The precise mechanisms underlying secondary brain damage after traumatic injury to the central nervous system (CNS) are not well understood, and delayed neuronal injury may result from pathological changes in neurotransmitter release, synthesis or generation of endogenous autodestructive neurochemicals and/or inflammatory mediators, or alterations in endogenous protective or trophic factors. Recent identification of such factors and the elucidation of the timing of the neurochemical cascade following CNS injury provides a window of opportunity for therapeutic intervention with pharmacological compounds which modify synthesis, release, receptor binding or physiological activity of neurotoxic factors. A number of recent experimental studies have reported that pharmacological modification of the post-traumatic neurochemical milieu can promote functional recovery in a variety of animal models of CNS trauma. This paper summarizes recent work suggesting that pharmacological manipulation of several key neurotransmitter and neurochemical systems can attenuate neuronal damage and improve functional outcome associated with traumatic brain injury.