A migraine is a neurological condition characterized by recurrent, severe headache attacks, often accompanied by symptoms like nausea, vomiting, and sensitivity to light and sound. When attacks become frequent or debilitating, a general practitioner often refers the patient to a neurologist. The neurologist is a specialist trained to diagnose complex headache disorders and develop comprehensive, long-term management strategies to reduce both the frequency and severity of attacks.
Comprehensive Evaluation and Diagnosis
The neurologist’s initial focus is a detailed diagnostic assessment to accurately classify the patient’s headache disorder. This relies heavily on a thorough medical history, documenting the frequency, duration, and severity of attacks, and the presence of an aura or other accompanying symptoms. This information allows the neurologist to apply the specific criteria outlined in the International Classification of Headache Disorders, 3rd Edition (ICHD-3).
A headache diary is an important tool, providing objective data on the number of headache days per month necessary to classify the condition as episodic or chronic. Chronic migraine is defined as experiencing headache on 15 or more days per month for over three months. The neurological examination checks for abnormalities but is typically normal.
Neuroimaging, such as an MRI or CT scan, is generally not required to confirm a migraine diagnosis. The neurologist orders these scans primarily to rule out secondary causes of headache that might mimic migraine symptoms. These causes include structural issues like tumors or aneurysms, which are only suspected when a patient presents with atypical features or a sudden change in their headache pattern.
Designing Acute Treatment Plans
Once a diagnosis is confirmed, the neurologist designs a strategic plan for treating an attack as soon as it begins (acute treatment). This involves differentiating between non-specific pain relievers and migraine-specific medications. Non-specific treatments include over-the-counter non-steroidal anti-inflammatory drugs (NSAIDs) and antiemetics.
Migraine-specific options are reserved for moderate to severe attacks and include triptans, ditans, and CGRP receptor antagonists (gepants). Triptans work by targeting serotonin receptors to constrict blood vessels and block pain pathways. Ditans and gepants are newer classes of medication used when triptans are ineffective or contraindicated, such as in patients with cardiovascular risk factors.
Specialist care includes counseling the patient on the risk of medication overuse headache (MOH). This condition occurs when the frequent use of acute pain relievers causes headaches to become more frequent. The neurologist advises patients to limit the use of acute medications to no more than ten days per month to prevent the transition to chronic migraine.
Implementing Preventative Strategies
For patients with frequent or disabling attacks, the neurologist implements preventative strategies. These involve taking a daily medication or receiving regular injections to reduce the overall frequency and severity of migraines. The initial approach often involves repurposing older medications originally developed for other conditions. These classes include anti-seizure medications, beta-blockers, and specific tricyclic antidepressants.
Finding the right oral preventative medication is often a process of trial and error. Patients must remain on a therapeutic dose for six to eight weeks before the neurologist can assess its effectiveness. Compliance is important because it can take several months to realize the full benefit of a new treatment. If these older oral options are ineffective or cause intolerable side effects, the neurologist considers a more targeted approach.
This targeted approach includes the newer CGRP monoclonal antibodies, the first medications developed specifically for migraine prevention. These medications are large molecules that target either the CGRP protein itself or its receptor, blocking pain signal transmission in the nervous system. Unlike older oral preventatives, these treatments have a long biological half-life, administered via subcutaneous injection or intravenous infusion, typically monthly or quarterly. This targeted mechanism often results in better tolerability and fewer systemic side effects, offering an advantage for patients who have failed multiple prior treatments.
Advanced Procedural Treatments
For patients whose chronic migraines have not responded to multiple oral medications and CGRP antibodies, the neurologist can administer advanced procedural treatments. These interventions are reserved for refractory cases and are performed in the clinic setting. The primary advanced preventative treatment is OnabotulinumtoxinA, commonly known as Botox, approved for chronic migraine prevention.
The treatment involves a series of small, shallow injections into 31 specific sites across seven areas of the head and neck. Botox works by blocking the release of chemicals involved in pain signal transmission at nerve endings, preventing the activation of pain networks in the brain. Treatments are cycled every 12 weeks and may take two or more cycles to yield a noticeable reduction in headache days.
Another in-office procedure is a nerve block, such as an occipital nerve block, used for temporary, targeted relief. This involves injecting a local anesthetic, sometimes with a corticosteroid, near a peripheral nerve. Nerve blocks can be used acutely to break a prolonged attack or diagnostically to determine the source of pain.