Effect of ceruletide on tardive dyskinesia: a pilot study of quantitative computer analyses on electromyogram and microvibration.

Seven patients with bucco-lingual dyskinesia were treated with a single dose of ceruletide 0.8 micrograms/kg IM, a potent analogue of cholecystokinin octapeptide. Time-course effects of the drug were then followed up to 6 weeks after injection in the longest case. To assess changes in severity of dyskinesia objectively, electromyogram and microvibration were recorded. These data were subjected to the Fast Fourier Transform and an averaged power spectrum was computed. The effect of ceruletide on dyskinesia within 2 h after injection differed (three cases: inhibitory, two cases: facilitatory, two cases: no effect). It was notable that a long-lasting inhibitory effect of this peptide was observed in two severe irreversible cases. The present findings might contribute to further understanding of the physiopathophysiological role of cholecystokinin-like peptides in the brain and to practical treatment of tardive dyskinesia.