Having a headache that lasts for days can sometimes be a warning sign of an impending stroke. While most headaches are not caused by anything serious, a persistent headache that is much worse than normal headaches should be evaluated by a doctor to rule out a stroke or other medical conditions.
What causes a headache before a stroke?
There are a few possible reasons why someone might have a headache for days leading up to a stroke:
- A brain aneurysm that is leaking or about to rupture can cause a severe headache. An aneurysm is a bulging blood vessel that can burst and cause bleeding in the brain, leading to a hemorrhagic stroke.
- A blood clot blocking an artery in the brain can cause headaches days before an ischemic stroke occurs. As the clot slowly cuts off blood flow, the lack of oxygen to brain cells can trigger headache pain.
- Very high blood pressure can damage blood vessels in the brain, causing them to leak or become inflamed. This can lead to a headache that persists for days before a hypertensive stroke happens.
- Inflammation of the blood vessel linings (vasculitis) from autoimmune conditions like lupus can cause headaches and increase stroke risk. The inflamed vessels are more prone to forming blood clots.
- Blood flow problems near the covering of the brain (the dura mater) may irritate pain-sensitive structures and cause a headache. Poor blood flow here raises the risk of stroke.
In most cases, the headache is thought to be referred pain that radiates from the damaged vessels or tissues surrounding the brain. As a stroke develops, the nerves and blood vessels become disturbed which signals the pain to the head.
What are the characteristics of a headache before stroke?
Headaches that warn of an impending stroke tend to have distinct features compared to regular headaches like migraines and tension headaches. Characteristics may include:
- New onset of headache that is much worse than normal headaches
- Constant headache that gets progressively worse over days
- Throbbing or stabbing pain, often on one side of the head
- Pain that worsens with position changes or straining
- Waking up with a headache that persists all day
- Headache with neurological symptoms like vision changes, numbness, or trouble speaking
- Headache unresponsive to over-the-counter pain medications
- Nausea and vomiting associated with the headache
While migraine can also cause an intense, throbbing headache with nausea, migraines tend to come and go in episodes rather than building in intensity over days. And migraine headaches are usually responsive to medications, unlike stroke-related headaches.
How long can a headache last before a stroke?
There is no set timeframe for how long headache symptoms will build before a stroke finally occurs. In some cases, the severe headache only develops in the 24-48 hours prior to the stroke. But many people report having a constant, moderate to severe headache for 5 days or more leading up to their stroke.
One study found that around 40% of stroke patients experienced a headache in the days before their stroke, with the average duration of headache being around 4 days. Only about 10% had a headache for less than 24 hours beforehand.
If you develop a headache that is strong, continuous and building in intensity over more than 2 days, it should not be ignored as it may be signaling an impending stroke.
Who is at risk of headache before stroke?
You may be at higher risk of developing a headache before a stroke if you have any of the following risk factors:
- Age over 50 years old
- High blood pressure
- Smoking or tobacco use
- High cholesterol
- Family history of stroke
- History of migraine headaches
- Use of birth control pills or hormone replacement therapy
- Sedentary lifestyle
- Excessive alcohol intake
- Illegal drug use
Those with vascular conditions like atherosclerosis, aneurysms, vasculitis or vascular malformations are also at increased risk of developing headache prior to stroke. Recent head trauma or neck injury can also make headache before stroke more likely.
When should you see a doctor for headache?
You should make an urgent appointment with your doctor if you develop any of the following:
- New onset of severe, constant headache
- Headache that keeps getting worse and does not respond to medication
- Headache that is accompanied by neurological symptoms like weakness, numbness, slurred speech, confusion or vision changes
- Headache that wakes you from sleep
- Headache with fever, neck stiffness or rash
Severe headache with neurological deficits requires prompt evaluation to determine if a stroke is imminent or already occurring. Even without other symptoms, a dramatically worsening headache over days warrants medical attention to look for underlying vascular issues.
Are there tests to diagnose headache before stroke?
If warning signs of stroke are present, the doctor may perform tests to help diagnose the cause of headache and determine if a stroke is impending. Tests may include:
- Neurological exam – checks vision, muscle strength, coordination and mental functioning
- Blood tests – measures electrolytes, glucose, and markers of inflammation to uncover underlying conditions
- CT or MRI scan – produces images of the brain to look for signs of bleeding or blockages
- Cerebrospinal fluid analysis – examines the fluid around the brain for infection or bleeding
- Angiogram – injects dye into the blood vessels to highlight flow in arteries supplying the brain
- Echocardiogram – uses ultrasound waves to check for cardiac sources of clots
Identifying the location, underlying cause and degree of disruption to blood flow in the brain will help determine the risk and timeline of stroke occurring.
How are headaches before stroke treated?
Treatment focuses on both relieving headache pain and preventing an imminent stroke. Options may include:
- Pain medications like acetaminophen or NSAIDs to alleviate headache
- Corticosteroids like dexamethasone to reduce inflammation of involved vessels
- Fibrinolytic drugs like tPA to break down clots before stroke occurs
- Surgical repair of aneurysms or vascular malformations that are causing bleeding
- Endovascular procedures to widen narrowed blood vessels
- Medications to lower blood pressure and prevent further damage
- Anticoagulant medications to prevent clot formation and enlargement
- Addressing underlying conditions such as infection, autoimmune disease, or trauma
If a stroke is occurring, emergency care focuses on dissolving or removing clots and getting blood flow restored quickly to save brain tissue. Rehabilitation helps regain function lost from the stroke.
Can you prevent a stroke after warning headaches?
When headaches signal high stroke risk, prevention is key. Steps to reduce your chances of having a stroke include:
- Taking medications to control high blood pressure or high cholesterol
- Starting a daily aspirin regimen if recommended by your doctor
- Quitting smoking and avoiding secondhand smoke
- Following a healthy diet low in salt, fat and refined sugars
- Reaching or maintaining a healthy weight
- Exercising for 30 minutes on most days of the week
- Limiting alcohol to 1-2 drinks per day maximum
- Managing stress through yoga, meditation or other relaxation techniques
- Treating sleep apnea or insomnia that disrupt oxygen levels
Catching the signs of stroke early and getting preventive care can significantly improve outcomes and reduce lasting disability.
In summary, developing a severe and persistent headache that continues getting worse over days can be a warning sign of an impending stroke in some cases. Anyone experiencing this should see a doctor right away for an evaluation. With prompt treatment, it may be possible to prevent a stroke from occurring or at least reduce the amount of damage. Being aware of headache and other stroke symptoms and getting preventive care remains vital for those at increased stroke risk.