Psychiatric Co-Morbidity and Botox for Chronic Migraine
Botox (onabotulinumtoxinA) was approved by the FDA in Septermber of 2010 for the treatment of chronic migraine.
The IHS definition of chronic migraine requires migraine symptoms with total headache days greater than 14 days each month for the previous three months. Most patients with chronic migraine have very close to continuous, if low grade, daily headache. The benefit of Botox in controlled trials was evident even in the absence of other treatments for migraine (such as treatment of medication overuse and caffeine related headache) or a general treatment program through a headache clinic.
At the North Carolina Comprehensive Headache Clinic, we have administered approximately 800 doses of Botox for migraine since 1993 with no serious complications.
Treating chronic migraine with Botox has been well tolerated, and when combined with general measures to treat chronic migraine, we have found it to be clinically useful. The selection criteria here is strict: other headache syndromes must be excluded (hemicrania continua, primary thunderclap headache, new persistent daily headache, cluster headache, hypnic headache, disorders of cerebrospinal fluid pressure, and headache secondary to other causes), medication and caffeine overuse withdrawn under supervision, and lack of efficacy of preventive medications documented before Botox is recommended.
The patient with chronic migraine and significant psychiatric co-morbidities presents complex diagnostic challenges and management difficulties. In patients with ongoing psychiatric care, adding psychotropic medications to treat chronic migraine as a separate condition may increase management complexity and patient risk. Concerns for the risk of serotonin syndrome, hyperthermia, suicide, inadvertent over-dosage, automobile accidents, and increase in metabolic complications (weight gain, hypertension, cardiac arrythmias, glucose intolerance) have previously significantly limited options for psychiatric patients.
Of all the groups of headache patients we see, we believe that the FDA approval of Botox will most benefit the care and management of the patient with chronic migraine and psychiatric co-morbidities.
For long-term management, Botox is administered only once every three months, which significantly reduces the need for Headache Clinic visits. Psychotropic medication may then be selected by the psychiatrist for optimal management of psychiatric conditions.
It is important to note that Botox has not been shown to benefit patients whose headache occurs less than 15 days/month.
We find that many patients with chronic headache “under count” their headache days, often because they do not wish to be seen as complaining of “normal” daily headache. We are also concerned that patients with true episodic migraine occurring less that 15 days/month will “over count” in hopes of obtaining Botox coverage. However, we feel it is well established that Botox will not benefit patients with intermittent migraine. Possibly, this is because Botox suppresses classical conditioning and kindling that may be involved in migraine transformation over time, thus allowing chronic migraine to be converted back to a more manageable intermittent migraine.
It is also important to note that Botox carries a black box warning and that patients should be selected appropriately.
Neurologists in our area that administer Botox can be found at the Allergan web site, or through the American Council on Headache Education. Patients may also be referred directly to NCCHC for neurological evaluation.