title: Alternating Horner's syndrome: is it or isn't it?
abstract: Two cases of so-called alternating Horner's syndrome are presented. Pupillary testing with cocaine and hydroxyamphetamine failed to reveal whether the problem was due to a lesion that shifted and thus had a truly alternating effect or whether it was due to a one-sided lesion that was at times hypoactive and at other times irritative.
mesh_terms: D000293:Adolescent; D000328:Adult; D003042:Cocaine; D006732:Horner Syndrome / Q000175:diagnosis*; D006801:Humans; D008297:Male; D011680:Pupil / Q000187:drug effects; D010136:p-Hydroxyamphetamine
chemical_list: D010136:p-Hydroxyamphetamine; D003042:Cocaine