An ischemic stroke is caused by a blood clot that interrupts blood flow in the brain. A hemorrhagic stroke is caused by a blood vessel that ruptures in the brain, causing blood to leak into surrounding brain tissue.

Strokes are a leading cause of death and disability. In the United States someone has a stroke about every 40 seconds, and somebody dies from a stroke every 3.5 minutes.

A stroke occurs when blood flow is interrupted to part of your brain. Reduced blood flow can lead to the death of brain tissue. The two most common kinds of stroke are ischemic stroke and hemorrhagic stroke. Both kinds of stroke are medical emergencies that need immediate treatment by calling 911 or local emergency services.

An ischemic stroke, which is the most common type, occurs when a blood clot blocks a blood vessel in your brain. Hemorrhagic strokes occur when a blood vessel in your brain ruptures.

Read on to learn more about the similarities and differences between ischemic and hemorrhagic strokes.

An illustration showing a cross section of the brain and how an ischemic stroke differs from a hemorrhagic stroke. The illustration shows an ischemic stroke being caused by a blood clot in an artery in the brain, while a hemorrhagic stroke is caused by a ruptured blood vessel in the brain.Share on Pinterest
Illustration by Jason Hoffman

According to the Centers for Disease Control and Prevention (CDC), ischemic strokes account for about 87% of the more than 795,000 strokes that occur in the United States each year.

The main cause of ischemic stroke is a blood clot that develops in an area where fatty plaque has built up inside your blood vessels.

Risk factors for ischemic stroke include:

An ischemic stroke can also be caused by arterial fibrillation. Arterial fibrillation is a condition characterized by an abnormal and often rapid heart rate in the atria: the upper chambers of your heart.

When the atria don’t contract in a regular rhythm, it can cause blood to pool in your heart. The pooling can cause a clot to form, which then travels through your arteries to your brain.

Ischemic stroke symptoms

Ischemic stroke symptoms can vary depending on where in your brain a stroke occurs. Here’s a look at some of the most common symptoms based on where the blockage happens.

Middle cerebral artery infarctionfacial paralysis
•weakness or paralysis on one side of your body
•loss of sensation in the face and arm
•gaze changes
difficulty pronouncing words
inability to remember words
Anterior cerebral artery infarction•loss of sensation or ability to move your leg on the opposite side of the stroke
Posterior cerebral artery infarctioninability to stay awake
•changes in your ability to see
total or partial loss of sensation in a body part
problems with muscle coordination
•altered sensation or ability to move one side of your body
Vertebrobasilar infarction•problems with muscle coordination
difficulty swallowing
•visual changes
•abnormal eye movements
Cerebellar infarction•problems with muscle coordination
slurred speech

Ischemic stroke treatment

The main treatment for ischemic stroke is usually a medication injected into your arm called “plasminogen activator (tPA)” that breaks up blood clots.

This medication is ideally administered within 3 to 4.5 hours after the onset of stroke symptoms, but tPA can be unsafe for people who have a high risk of internal bleeding.

You may also need surgery to break up a blood clot through a thrombectomy or carotid endarterectomy.

A thrombectomy is the removal of the blood clot with a special tube threaded through a blood vessel in your thigh until it reaches the blocked artery. A surgeon will then use a stent or a special balloon to open your blood vessel.

A carotid endarterectomy is the removal of plaque from the large carotid artery in your neck. You may need this procedure if it’s found that carotid artery disease contributed to your stroke.

Hemorrhagic strokes make up about 10% of strokes, which is equivalent to about 79,500 strokes per year in the United States. These strokes are caused by bleeding in the brain from a ruptured blood vessel. High blood pressure is the most common underlying cause.

Other risk factors include:

Symptoms of hemorrhagic stroke

Symptoms of hemorrhagic stroke typically come on quickly and may include:

  • severe headache
  • paralysis on one side
  • facial numbness or loss of movement on one side
  • trouble speaking
  • problems with coordination
  • muscle weakness or paralysis
  • vomiting
  • neck stiffness
  • increased blood pressure
  • seizure
  • partial blindness
  • visual changes
  • drooping eyelids

Hemorrhagic stroke treatment

It’s vital to receive medical treatment as soon as possible. Getting treatment early on gives you the best chance of making a good recovery. Treatment will depend on where the blood vessel rupture occurred and the severity of the bleeding.

Treatment options for a hemorrhagic stroke include:

  • Medications: Medications will vary, and the type of medication that’s most appropriate will depend on whether you’re currently taking any anticlotting or blood-thinning medications and which type. You may receive hemostatic agents (substances to control or stop bleeding) or medications to reverse blood thinning.
  • Aneurysm clipping: A clamp is placed at the base of a bulge in a blood vessel in the brain to stop bleeding.
  • Coil embolization: A tube is inserted into an artery in your groin, and a tiny coil is pushed through until it reaches the ruptured blood vessel.
  • Blood transfusion: Lost blood is replaced with blood from a donor.
  • Draining excess fluid: A stroke can cause fluid buildup in your brain. A surgeon may need to drain this fluid to relieve pressure on brain tissue.
  • Surgery to remove pooled blood: A surgeon may need to remove pooled blood if your symptoms are getting worse.
  • Removal of part of your skull: Temporarily removing part of your skull may help to relieve pressure in your brain.
  • Surgery to remove arteriovenous malformation: An arteriovenous malformation is a tangle of blood vessels that can bleed in the brain, and it may need to be removed surgically.

A transient ischemic attack (TIA), also called a “ministroke,” is a temporary blockage in the blood supply to the brain. TIAs can cause similar symptoms as a stroke, but the symptoms tend to resolve fully within 24 hours. TIAs are considered a major risk factor for a stroke.

The symptoms of a TIA and a stroke can be almost identical. Even if your symptoms resolve on their own, it’s important to get medical attention to figure out what caused the TIA. Getting treatment for the underlying cause of a TIA may help lower your risk of a more serious stroke down the road.

Strokes can cause a wide range of symptoms depending on where they happen in your brain. Symptoms can be similar between ischemic and hemorrhagic strokes, but hemorrhagic strokes are more likely to cause a sudden or severe headache.

In a 2017 study, researchers found the following differences in prevalence between ischemic and hemorrhagic stroke symptoms in a group of 503 people:

SymptomIschemic (%)Hemorrhagic (%)
Eye gaze impairment6.745.1
Dilated pupils27.486.8
Unequal pupil size06.9

One of the key factors with a stroke is how quickly you get treatment. The sooner treatment starts, the better the outlook for a person who has had a stroke regardless of the type of stroke.

The outlook for people with ischemic stroke is generally considered better than people with hemorrhagic stroke, but studies that look at the rates of recovery between the two types of stroke have found mixed results.

In a 2021 study, researchers found that hemorrhagic stroke is linked to worse functional and clinical outcomes compared with ischemic strokes at discharge from the intensive care unit. On average, people who have hemorrhagic stroke tend to be younger and need longer and more intensive hospitalization.

Strokes are a very common cause of disability and death in the United States. Ischemic strokes are the most common type of stroke.

Ischemic strokes occur when a blood clot blocks blood flow in your brain. Hemorrhagic strokes occur when a blood vessel in your brain ruptures.

Both types of stroke share many of the same symptoms, such as muscle weakness, paralysis on one side of the body, trouble speaking, lack of coordination, and visual changes.

Both ischemic and hemorrhagic strokes are medical emergencies that require immediate attention. The sooner treatment is started, the higher the chance of a positive outcome.