The pharmacologic treatment of migraine may be acute (abortive) or preventive (prophylactic), and patients with frequent severe headaches require both approaches. Effective migraine treatment begins with making an accurate diagnosis, ruling out alternate causes, and addressing the headache’s impact on the patient; educating the patient with regard to treatment options, side effect profi le, duration of therapy, and expectations for improvement; and developing a treatment plan that considers coincidental and comorbid conditions. Conditions that occur in patients with migraine with a higher prevalence than coincidence include stroke, comorbid pain disorders, angina, patent foramen ovale (aura), epilepsy, and certain psychiatric disorders, which include depression, mania, anxiety, and panic disorder.
Principles of migrain preventive treatment are important to improve compliance, minimize side effects, and improve patient outcomes, reduce the frequency, duration, or severity of attacks and reduce health care costs. Additional benefits may include enhancement of response to acute treatments, improvement of a patient’s ability to function, and reduction of disability. Moreover, the choice of preventive treatment of migraine should be based on the presence of comorbid and coexistent illness, patient preference, reproductive potential and planning, and best available evidence. A preventive migraine drug is considered successful if it reduces migraine attack frequency or days by at least 50% within 3 months. Migraine preventive drugs with the best proven effi cacy are certain ß-blockers, divalproex sodium, and topiramate.
Although monotherapy for migraine prevention is preferred, it often does not yield the desired therapeutic effect, and it may be necessary to combine preventive medications. Moreover, ß-blockers are the most widely used class of drugs in prophylactic migraine treatment and are about 50% effective in producing a greater than 50% reduction in attack frequency. Evidence has consistently demonstrated the effi cacy of the nonselective ß-blocker propranolol and of the selective beta1-blocker metoprolol. Beta-blockers with intrinsic sympathomimetic activity (e.g., acebutolol, alprenolol, oxprenolol, pindolol) are, however, not effective for migraine prevention. Evidence-based guidelines for the preventive treatment of migraine have recently been published by the American Academy of Neurology (AAN) and the Canadian Headache Society (CHS), providing valuable guidance for clinicians. Strong evidence exists to support the use of propranolol, among others, for migraine prevention, according to the AAN. Based on best available evidence, adverse event profi le, and expert consensus, propranolol is one of the beta-blockers along with topiramate, amitriptyline, gabapentin, candesartan, ribofl avin, coenzyme Q10, and magnesium citrate, which received a strong recommendation for use from the CHS.
Patients may relapse after the discontinuation of preventive migraine treatment; therefore, they should be cautioned in this regard and followed carefully for escalating attack frequency. To summarize, preventive therapy plays an important role in migraine management. When a preventive medication is added, attack frequency may be reduced and response to acute treatment improved, which can result in reduced health care resource utilization and improved quality of life. Despite research suggesting that a large percentage of patients with migraine are candidates for prevention, only a fraction of these patients are receiving or have ever received preventive migraine medication.
GP CLINICS vol 7 no 10, January 2017 Page 66