[Effect of neurotropin on chronic headaches in children].
ABSTRACT We report the cases of 2 girls, aged 13 and 15 years, who experienced exacerbation of migraine at 2-3 years after its onset. The chronic headaches were refractory to various anti-migraine and analgesic agents, persisted for 3-6 months in each patient, and rendered them unable to attend school. These headaches commonly manifested with symptoms of orthostatic dysregulation and paroxysmal back/limb pain. In addition, T2-weighted magnetic resonance images showed dots of highly intense signals in the bilateral cerebral white matter. Neurotropin, a non-protein extract isolated from the dermis of rabbits and inoculated with the vaccinia virus, induced prompt significant effects on the headache and back/limbs pain in both the girls. The symptom of orthostatic dysregulation was also gradually ameliorated after the resolution of the headache. Neurotropin has an analgesic action that is not common to other drugs since it enhances the descending pain inhibitory systems, and its effect has been reported in cases of post-herpetic and other neuralgia as well as in cases of primary headaches in adulthood. This agent may also be promising for the treatment of intractable primary headaches during childhood.