Migraine

Definition

Migraine is a common primary headache disorder characterised by recurrent attacks of moderate to severe headache. The headache is often unilateral, pulsating, and aggravated by physical activity. It is typically associated with nausea, vomiting, and sensitivity to light (photophobia) and sound (phonophobia).

Aetiology

The exact cause of migraine is not fully understood, but it is believed to be related to genetic and environmental factors. Triggers may include hormonal changes, certain foods and drinks, stress, sensory stimuli, changes in sleep patterns, and physical exertion.

Pathophysiology

Migraine is thought to involve a complex interplay between neuronal and vascular mechanisms. The trigeminovascular system plays a key role, where activation leads to the release of neuropeptides such as calcitonin gene-related peptide (CGRP), causing vasodilation and inflammation of the meninges. This results in the characteristic pain and associated symptoms of migraine.

Risk factors

Family history of migraine
Female gender (hormonal changes related to menstruation, pregnancy, and menopause)
Age (most common in people aged 15-55)
Certain medical conditions (e.g., depression, anxiety, epilepsy, sleep disorders)
Lifestyle factors (stress, irregular sleep, dietary triggers)

Signs and Symptoms

Unilateral, pulsating headache
Nausea and vomiting
Photophobia (sensitivity to light)
Phonophobia (sensitivity to sound)
Aura (visual disturbances, sensory changes) in some cases
Aggravation by physical activity

Red Flags

Sudden onset of severe headache (thunderclap headache)
New headache in individuals over 50
Headache with systemic symptoms (fever, weight loss)
Neurological symptoms (focal neurological deficit, altered mental status)
Headache triggered by coughing, sneezing, or physical exertion
Progressive headache worsening over time

Investigations

Clinical history and physical examination, including neurological examination (cranial nerves, motor and sensory function, reflexes, coordination)
Neuroimaging (MRI or CT scan) if there are red flags or atypical symptoms
Blood tests to rule out other causes
Referral to an optician to rule out raised intracranial pressure (ICP)

Management

Primary Care Management:

Acute treatment with triptans (e.g., sumatriptan 50-100 mg) at the onset of headache
Nonsteroidal anti-inflammatory drugs (NSAIDs) such as ibuprofen (400-600 mg) or aspirin (900 mg)
Paracetamol (1000 mg) for pain relief
Antiemetics (e.g., metoclopramide 10 mg) for nausea and vomiting
Prophylactic treatment for frequent migraines, such as beta-blockers (e.g., propranolol), anticonvulsants (e.g., topiramate), or amitriptyline
Referral to a headache clinic or neurology if primary treatment fails
Education on lifestyle modifications to avoid known triggers

Example Management for Acute Migraine:

A patient presenting with an acute migraine attack may be advised to take sumatriptan 50 mg as soon as the headache starts. If the headache persists after two hours, a second dose of sumatriptan may be taken (maximum 100 mg in 24 hours). Additionally, the patient can take ibuprofen 400 mg to help alleviate the pain. If nausea is a significant symptom, metoclopramide 10 mg can be used to relieve it. For prophylactic treatment if migraines are frequent, amitriptyline can be considered, starting at 10-25 mg at night, increasing gradually based on response.

References:

NICE. (2023). Migraine: Management. Retrieved from https://cks.nice.org.uk/topics/migraine/management/
NICE. (2023). First in new class of treatment for acute migraine recommended by NICE. Retrieved from https://www.nice.org.uk/news/article/first-treatment-for-acute-migraine-to-be-recommended-by-nice-set-to-benefit-thousands
CKS NICE. (2023). Migraine in adults: management. Retrieved from https://cks.nice.org.uk/topics/migraine/management/adults/
O'Sullivan, S. B., & Schmitz, T. J. (2016). Physical Rehabilitation. 6th ed. F.A. Davis Company.
Ropper, A. H., & Samuels, M. A. (2019). Adams and Victor's Principles of Neurology. 11th ed. McGraw-Hill Education.