There are at least seven tachykinins in the human body, and their actions are diverse. Tachykinins are predominantly excitatory, in the brain (presynaptic enhancement of glutamate release), and enhance motility in the gut and inflammation in many tissues. Substance P and neurokinin B are involved in status epilepticus, and are overexpressed in the mossy fibers, the axons of hippocampal granule cells, after intense seizure activity. Their antagonists are among the most potent inhibitors of established status epilepticus, but have not so far been developed for clinical use. Our understanding of the physiological functions of tachykinins is still fragmentary, and we need more studies of the physiological and pathological roles that tachykinins play in the human brain and in human epilepsy.