A method for selection and treatment of externally caused migraine headache, the method includes identifying a patient group having chronic migraine headache; determining the identified patient group, a specific patient with a post traumatic migraine headache; and administering to the selected patient by injection of a therapeutically effective amount of an invertebrate presynaptic neurotoxin in a pharmaceutically safe form to the selected patient's head or upper neck; administration preferably being on the sites of the trigeminal cervical system, enabling axonal transport of the neurotoxin from distal to central sites; and the administration preferably comprising extramuscular injection of the neurotoxin of suitable dilution (a) over the aponeurotic fascia to enable the neurotoxin to diffuse into distal sensory nerves, in order to concentrate the neurotoxin over the occipital-parietal-frontal head region, or (b) intra-orally, in a foramina of the sphenopalatine ganglion for enabling diffusion of the neurotoxin to the ganglion, or (c) to emerging exit points of nerves including foraminal sites for enabling the neurotoxin access to concentrated nerve bundles at exit points of the foramina.