A concussion can cause a migraine-like headache, a common clinical phenomenon following head trauma. A concussion is medically classified as a mild traumatic brain injury (mTBI), resulting from a blow or jolt to the head or body that causes the brain to move rapidly inside the skull. This movement temporarily disrupts normal brain function. One frequent consequence is a headache that shares characteristics with primary migraine disorder. Up to 95% of people who sustain a concussion experience a headache in the days or weeks following the event. Approximately two-thirds of these headaches feature strong migraine characteristics.
Defining Post-Traumatic Headache
The clinical term for any headache disorder that arises after a head injury is Post-Traumatic Headache (PTH). To be classified as PTH, the headache must begin within seven days of the trauma or within seven days of regaining consciousness. This temporal relationship establishes the injury as the cause. PTH is an umbrella classification that manifests with various features, most often resembling a tension-type headache or a migraine. The migraine-mimicking phenotype is common and often debilitating. Duration determines sub-classification: acute PTH resolves within three months, while persistent PTH lasts three months or longer, guiding long-term management.
The Biological Mechanism Behind Concussion Headaches
The physical force of a concussion initiates a complex cascade of chemical and electrical changes in the brain that directly contribute to the migraine-like pain. The initial impact causes an unregulated release of excitatory neurotransmitters, such as glutamate, which overstimulate neurons. The rapid influx and efflux of ions, including potassium and calcium, results in an energy crisis: the brain demands high energy to restore balance but has a reduced ability to supply it.
This disruption can trigger Cortical Spreading Depression (CSD), a wave of intense electrical activity traveling across the cortex. CSD is a known mechanism for migraine with aura, and its post-concussion occurrence is believed to trigger headache pain. The CSD wave releases inflammatory molecules and causes further neurotransmitter imbalances, sustaining pain signals.
The trauma and chemical changes also activate the trigeminal nerve system, the major pain pathway for the head and face. This activation involves neuroinflammation, where immune cells like microglia release inflammatory cytokines. These messengers sensitize the trigeminal nerves innervating the meninges, leading to a lowered pain threshold and chronic pain signals similar to primary migraine disorders.
Identifying Specific Migraine Symptoms
A post-concussion headache with a migraine-like presentation is more intense and debilitating than a standard tension headache. The pain is often throbbing or pulsating and frequently localized to one side of the head (unilateral pain). This quality indicates underlying neurovascular changes associated with migraine.
Heightened sensory sensitivity is a hallmark of post-concussion migraine. Patients experience photophobia (intolerance to light) and phonophobia (sensitivity to sound). These sensitivities result from disrupted communication pathways and make daily activities difficult.
These headaches are also accompanied by digestive symptoms, including nausea and sometimes vomiting. The pain is often aggravated by physical activity or exertion, requiring rest in a dark, quiet environment. Worsening headache, repeated vomiting, or confusion are warning signs requiring immediate medical attention.
Strategies for Management and Recovery
Initial management focuses on brief physical and cognitive rest, typically limited to the first 24 to 48 hours. Prolonged, strict rest is often counterproductive and can delay recovery, so gradual re-engagement in light activity is encouraged soon after the injury. Over-the-counter non-steroidal anti-inflammatory drugs (NSAIDs) or acetaminophen can be used for acute pain relief, but caution must be exercised to avoid overuse, which can lead to a secondary Medication Overuse Headache (MOH).
For more severe or frequent post-concussion migraines, a healthcare provider may prescribe abortive medications like triptans, which are common treatments for primary migraines. Preventive strategies are also important, including:
- Maintaining strict sleep hygiene.
- Managing stress.
- Identifying and avoiding specific headache triggers such as certain foods or excessive screen time.
- Physical therapy, particularly for co-occurring neck pain, as muscle tension often contributes to the headache profile.
If headaches persist or become chronic (lasting beyond a few weeks), consulting a neurologist or a concussion specialist is highly recommended. These specialists can evaluate the headache phenotype and determine if preventive medications, such as certain antidepressants or anti-seizure drugs, are appropriate to reduce the frequency and severity of the attacks. A comprehensive approach that paces activity and addresses all symptoms, not just the pain, offers the best path toward recovery.