Tyramine activates the EEG in epileptic patients

Abstract

IT has been suggested that abnormalities of monoamine metabolism may be important in migraine¹, and Sandler et al.² have demonstrated a reduction in monoamine oxidase activity in these patients. This observation might explain Hanington's finding¹ that an oral tyramine load could induce headache in selected individuals. These subjects had noticed that certain foods known to contain tyramine, such as cheese, regularly induced their migraine headaches. Although unable to confirm that single doses of oral tyramine regularly precipitated headache³ we have shown that this amine accentuates pre-existing electroencephalogram (EEG) abnormalities in subjects with dietary-induced migraine alone, and in a group of patients who had both migraine and epilepsy, but not in a group with non-dietary migraine. These observations suggested that the effect of tyramine on the EEG should be studied in patients with epilepsy alone. Furthermore, a preliminary investigation had indicated that tyramine caused an increased number of spikes in the EEG recordings of monkeys with alumina-induced epileptic foci⁴.