A hemorrhagic stroke happens when a blood vessel in or around the brain ruptures, causing bleeding that damages brain tissue. It accounts for roughly 35% of all strokes, with the remaining 65% caused by blockages (ischemic strokes). Though less common, hemorrhagic strokes are more deadly: about half of people with bleeding directly in the brain die within the first month.
Two Types of Hemorrhagic Stroke
Hemorrhagic strokes are classified by where the bleeding occurs. The distinction matters because the causes, symptoms, and treatments differ.
Intracerebral hemorrhage is the more common type. A blood vessel inside the brain itself bursts, and blood leaks directly into the surrounding brain tissue. The pooling blood forms a clot that puts pressure on nearby cells, cutting off their oxygen and killing them. Globally, intracerebral hemorrhage accounts for about 29% of all strokes.
Subarachnoid hemorrhage involves bleeding in the narrow space between the brain and the thin membranes that cover it. This type makes up about 6% of all strokes and is most often triggered when a weak, ballooned-out spot on an artery (an aneurysm) ruptures on the brain’s surface.
What Causes a Blood Vessel to Rupture
Chronic high blood pressure is the single biggest driver of intracerebral hemorrhage. Years of elevated pressure gradually weaken the walls of small arteries deep in the brain until one gives way. This is why aggressive blood pressure management is central to both prevention and acute treatment.
Aneurysms cause most subarachnoid hemorrhages. These balloon-like bulges can sit quietly on a brain artery for years, then rupture without warning. Some people are born with a tendency to develop them; smoking and high blood pressure accelerate the process.
Arteriovenous malformations (AVMs) are another cause, especially in younger patients. AVMs are tangles of abnormally formed blood vessels where arteries connect directly to veins without the usual network of tiny capillaries in between. Because they lack that buffer, the vessels are fragile and prone to bursting. A related condition, cavernous malformations, involves clusters of enlarged, slow-flow capillaries that can also bleed, though usually less severely.
Blood-thinning medications raise the risk as well. People taking anticoagulants for heart conditions or blood clots have a higher chance of bleeding if a vessel does weaken. When hemorrhagic stroke occurs in someone on blood thinners, reversing the medication’s effects quickly is a critical part of emergency treatment.
Symptoms and How to Recognize Them
The hallmark symptom of a hemorrhagic stroke, particularly a subarachnoid hemorrhage, is a thunderclap headache: a sudden, explosive pain that people often describe as the worst headache of their life. It peaks within seconds rather than building gradually.
Other symptoms overlap with those of any stroke but can appear alongside signs of rising pressure inside the skull:
- One-sided weakness or paralysis in the face, arm, or leg
- Slurred speech or difficulty finding words
- Sudden vision changes or loss in one or both eyes
- Dizziness or loss of balance
- Sensitivity to light
- Neck stiffness (common with subarachnoid hemorrhage)
- Nausea and vomiting
- Seizures
- Loss of consciousness or coma
The BE FAST acronym is a practical way to spot a stroke in someone else. Check for sudden loss of Balance, Eye or vision changes, Facial drooping on one side, Arm weakness (ask them to raise both arms and watch for one that drifts down), and Speech problems. The T stands for Time, because every minute of bleeding increases the damage.
What Happens in the Emergency Room
Speed matters even more with hemorrhagic stroke than with a blockage-type stroke, because blood continues to leak and pressure inside the skull keeps climbing. The first step is a CT scan to confirm bleeding and pinpoint its location. From there, treatment focuses on two immediate goals: stopping the bleed and reducing pressure on the brain.
Bringing blood pressure down quickly is a priority. Guidelines recommend lowering systolic pressure (the top number) to under 140 mmHg within the first hours. Trials involving thousands of patients have shown that hitting this target, compared to allowing pressure to stay below 180, is associated with better outcomes.
If the person is on blood thinners, the medical team works to reverse those drugs as fast as possible. Getting anticoagulation reversed within four hours, combined with blood pressure control, significantly reduces the chance that the bleeding will expand and lowers the risk of dying in the hospital.
Surgical Options
Not every hemorrhagic stroke requires surgery, but when it does, the approach depends on what caused the bleed.
For ruptured aneurysms, two main procedures can seal off the weak spot. In one approach, a surgeon places a tiny metal clip at the base of the aneurysm to shut off blood flow to it. In the other, called endovascular coiling, a thin catheter is threaded from an artery in the groin up to the brain. Tiny platinum coils, some as thin as a human hair, are packed into the aneurysm through the catheter. The coils trigger clotting inside the aneurysm, sealing it from the inside. Sometimes a small mesh stent is placed alongside the coils to keep them from shifting.
When a large clot is putting dangerous pressure on the brain, surgeons may need to drain the blood directly. In severe cases, a section of skull may be temporarily removed to give swollen brain tissue room to expand without being crushed. That bone flap is replaced later once swelling resolves.
Recovery and Long-Term Outlook
Hemorrhagic stroke carries a grim early mortality rate. Roughly half of people with intracerebral hemorrhage do not survive the first month. Survivors, however, have a surprisingly encouraging recovery trajectory compared to people who had blockage-type strokes of similar severity.
In one matched comparison study, hemorrhagic stroke survivors who went through inpatient rehabilitation were about 2.5 times more likely to achieve a strong functional recovery than ischemic stroke patients with comparable deficits. By the time they were discharged from rehab, hemorrhagic stroke patients had made significantly greater gains in neurological function, mobility, and independence with daily activities. They also had notably lower rates of lasting incontinence (about 5% versus 12% in the ischemic group).
This pattern likely reflects the nature of the injury. A blockage kills brain cells permanently by starving them of oxygen. With a hemorrhage, some of the damage comes from pressure and swelling rather than outright cell death. As the blood is reabsorbed and swelling subsides, brain tissue that was compressed but not destroyed can begin working again.
Recovery timelines vary widely depending on the size and location of the bleed, the person’s age, and how quickly they received treatment. Most of the fastest improvement happens in the first three to six months, though gains can continue for a year or more with consistent rehabilitation. Physical therapy, occupational therapy, and speech therapy are the core pillars of recovery for most survivors.
Reducing Your Risk
Because high blood pressure is the dominant cause of hemorrhagic stroke, keeping it in a healthy range is the single most effective thing you can do. That means regular monitoring, staying physically active, limiting sodium, and taking prescribed blood pressure medication consistently.
Smoking weakens blood vessel walls and promotes aneurysm formation. Quitting substantially lowers the risk. Heavy alcohol use is another independent risk factor, as it both raises blood pressure and impairs the blood’s ability to clot properly.
If you’re on blood-thinning medication, staying within the prescribed dose and attending regular follow-up appointments matters more than most people realize. The benefit of anticoagulants for preventing clot-based strokes and heart attacks is real, but the dosing needs to be right to avoid tipping the balance toward bleeding risk.