CHAPTER 33: Headache Therapeutics

INTRODUCTION TO HEADACHE THERAPEUTICS

Headache is one of the most common complaints among patients presenting to an outpatient practice. Once secondary causes of headache are excluded and a primary headache diagnosis has been established, selecting appropriate pharmacotherapy can be a very complex process. Medications must be tailored to each patient's unique combination of comorbidities and lifestyle considerations. In this chapter, treatment strategies for some of the more common primary headache disorders are reviewed. This discussion will focus on migraine, tension-type headache (TTH), and the trigeminal autonomic cephalalgias (TACs). Our discussion of TACs will include cluster headache, paroxysmal hemicrania, short-lasting unilateral neuralgiform headaches with conjunctival injection and tearing or autonomic features (SUNCT/SUNA), and hemicrania continua.

MIGRAINE HEADACHE TREATMENT

ABORTIVE MIGRAINE TREATMENT

Nonsteroidal anti-inflammatory medications (NSAIDs), triptans, dihydroergotamine, and antiemetics are the mainstays of abortive treatment for migraine headaches. Other commonly used, nonspecific analgesics include acetaminophen, aspirin, cyclooxygenase-2 inhibitors, opiates, and combination analgesics. In general, opiates and most combination analgesics are avoided due to the high potential for medication overuse headaches.

NSAIDs are some of the most commonly used and effective first-line agents for abortive migraine treatment. They can be used as monotherapy or in combination with other medications.^2,3 Commonly used NSAIDs include ibuprofen, naproxen sodium, diclofenac, ketoprofen, and ketorolac. These drugs are relatively inexpensive, readily available, and are available in a variety of administration routes. For example, intravenous ketorolac is often used in the emergency department setting, but it is also available in tablet form and as an intranasal spray. Renal toxicity is an important side effect with any NSAID, but extra caution should be exercised with ketorolac use. Diclofenac is available in tablet form, but it also comes in a powdered form for oral solution that has proven efficacy in acute migraine.⁴ In addition to nephrotoxicity, NSAIDs as a class are associated with dyspepsia and fluid retention. It is important to note that NSAIDs carry U.S. Food and Drug Administration Black Box warnings for cardiovascular risks, gastrointestinal ulceration, and bleeding risks. Despite these risks, moderate NSAID use is generally quite well tolerated.

Several different triptans are available for the treatment of migraines (Table 33-1). As a class of medications, the differences between oral triptans are relatively small, but the effects can vary among individual patients.⁵ When choosing a triptan, it is important to consider the formulary coverage and costs associated with an individual's insurance plan. Sumatriptan, naratriptan, zolmitriptan, and rizatriptan are currently the only generic triptans on the market. Sumatriptan has been a generic medication longer than any other triptan and is almost universally the preferred triptan from an insurance coverage standpoint. Studies have demonstrated that triptan use decreases as copayment increases. In addition, demand for pharmaceuticals was relatively unchanged with copayment increases.⁶