What Happens in the Brain During the Headache Phase?
The headache phase is driven by a complex cascade of neurochemical and vascular (blood vessel) changes triggered by trigeminal nerve activation.
- The trigeminal nerve releases CGRP (calcitonin gene-related peptide), an inflammatory pain-signaling chemical that dilates blood vessels around the brain and amplifies pain signals
- Dilated blood vessels activate pain-sensitive nerve endings surrounding the brain, producing the characteristic throbbing pain of migraine
- Central sensitization (increased nervous system sensitivity to pain) develops progressively during the headache phase, making the brain increasingly reactive to normally non-painful stimuli such as touch or movement
- Serotonin levels drop sharply during the headache phase, sustaining blood vessel dilation and prolonging pain
What Are the Symptoms of the Headache Phase?
Core Headache Symptoms
- Moderate to severe throbbing or pulsating pain, typically on one side of the head
- Pain worsening with routine physical activity such as walking, climbing stairs, or bending forward
- Attacks lasting between 4 and 72 hours without treatment
- Pain severe enough to prevent or significantly limit normal daily activities
Associated Symptoms
- Nausea with or without vomiting
- Photophobia (sensitivity to light)
- Phonophobia (sensitivity to sound)
- Osmophobia (sensitivity to smell) in some individuals
- Allodynia (pain from normally non-painful stimuli such as touching the scalp, wearing glasses, or brushing hair) affects up to 70% of people during the headache phase, according to Headache Journal (2021)
Cognitive and Physical Symptoms
- Difficulty concentrating or thinking clearly
- Dizziness or a feeling of unsteadiness
- Nasal congestion or a runny nose
- Paleness and cold hands or feet due to autonomic nervous system changes
- Extreme fatigue and weakness
How to Manage the Headache Phase?
Step-by-Step Acute Management
- Take prescribed acute migraine medication at the earliest sign of headache onset for the best response
- Move to a quiet, dark room and lie down with minimal physical movement
- A cold compress on the forehead or back of the neck helps to reduce the severity of the pain
- Drink water regularly and stay hydrated, especially if there is nausea and vomiting
- Avoid situations with screens, light, and noise until the migraine subsides
- Notify others around you of an impending migraine to reduce pressures and stressors on you
Acute Medications
- Triptans, which include sumatriptan and rizatriptan, are the best acute medications, which act by constricting dilated blood vessels and inhibiting the release of CGRP. They are best used within the first 30-60 minutes of headache onset.
- NSAIDs, which include ibuprofen and naproxen sodium, are best used for mild to moderate headaches
- attacks and work by reducing prostaglandin-driven (inflammatory chemical) pain and inflammation
- CGRP antagonists (gepants) such as ubrogepant are a newer class of acute medications that directly block the CGRP pathway with fewer side effects than triptans for some individuals
- Antiemetics such as Metoclopramide helps relieve nausea and vomiting and enhance absorption of oral pain medications taken during the attack
Why Timing of Treatment Matters?
- Taking acute medication within the first 30 to 60 minutes of headache onset significantly improves treatment effectiveness
- Delaying treatment allows central sensitization to develop, making the headache harder to treat and more likely to last the full 4 to 72 hours
- Taking acute medications more than 10 days per month leads to medication overuse headache (MOH), a rebound condition that worsens overall migraine frequency over time
Headache Phase Triggers to Avoid
During the headache phase, specific activities or environmental factors can increase headache discomfort and prolong headache duration.
- Bright or flickering lights, including screen time, fluorescent lighting, and natural sunlight
- Loud noises, including music, television, and human voices
- Pungent odors, including perfumes, food scents, and cleaning agents
- Physical activities, including exercise, lifting, or moving quickly
- Alcohol and caffeine, both of which can intensify headache pain and prolong the attack
When Should You Seek Emergency Care During the Headache Phase?
Most migraine headache phases can be managed at home. However, seek immediate emergency medical attention if:
- The headache is described as the worst headache of one's life or reaches peak intensity within seconds (thunderclap headache)
- A headache is associated with fever, stiff neck, confusion, or rash, suggesting meningitis
- One-sided weakness, speech difficulty, or vision loss accompanies the headache
- The headache phase lasts longer than 72 hours without any relief, a condition called status migrainosus
- Acute medications have been taken, but symptoms are rapidly worsening rather than improving
Conclusion
The headache phase is the most painful and disabling stage of a migraine attack, driven by trigeminal nerve activation, CGRP release, and central sensitization. Throbbing pain on one side, nausea, and sensitivity to light and sound are the defining features. Taking prescribed acute medication within the first 30 to 60 minutes of headache onset, resting in a dark and quiet environment, and staying hydrated are the most effective strategies for managing the headache phase. Avoiding medication overuse and seeking emergency care for red flag symptoms are equally important aspects of safe headache phase management.
