Calcitonin Gene-related Peptide Levels in Chronic Migraine

"Minimum dose of 155 U OnabotulinumtoxinA Purified Neurotoxin Complex administered at 31 fixed-site, fixed-dose injections across seven specific head/neck muscle areas. Subjects will continue to monitor headache symptoms with a headache diary and collect saliva samples as instructed.~At investigator's discretion, additional 40 U OnabotulinumtoxinA Purified Neurotoxin Complex may be administered unilaterally or bilaterally, using follow-the-pain paradigm."

"155 U Saline administered at 31 fixed-site, fixed-dose injections across seven specific head/neck muscle areas. Subjects will continue to monitor headache using a headache diary and collect saliva samples as instructed.~At investigator's discretion, additional Saline may be administered unilaterally or bilaterally, using follow-the-pain paradigm."