Signs of Stroke

A stroke occurs when not enough blood reaches the brain. Blood flow to the affected part or parts of the brain may be partially obstructed or cut off completely. There are two different ways a stroke can occur: 1

• Ischemic stroke, in which the flow of blood to the brain is blocked or obstructed by a blood clot or fatty deposit, or any mix thereof. Four out of five strokes are ischemic 2
• Hemorrhagic stroke, in which there is bleeding within the brain or on the surface of the brain

Emergency services should be called immediately if a stroke is suspected. The quicker a stroke is treated, the more likely doctors will be able to manage the symptoms well and with the best possible outcome for the person involved.

An acronym, F.A.S.T., explains the telltale signs that a stroke is very likely to be happening: 1 2

• Face. The face suddenly becomes weak or droopy, with the effect usually more visible on one side
• Arm. One arm suddenly becomes numb or weak, and there may be difficulty raising it
• Speech. Speaking becomes difficult, and the affected person’s voice becomes slurred. They may be hard to understand, and what they say may not make much sense
• Time to call. If any of the above is noticed, the emergency services should be called immediately

For example, call:

• 911 in the U.S. and Canada
• 112 in most European countries
• 999 in the U.K.

Strokes are complex, and only one of the above signs may be present. Nevertheless, one sign of stroke on its own is enough to indicate that a person should receive medical treatment without delay.

Some other common signs of stroke include the following suddenly happening: 3 4

• Confusion or trouble understanding what others are saying
• Difficulty seeing or other visual problems
• Dizziness
• A loss of balance or coordination, and difficulty walking
• A sudden severe headache, with no known cause
• Short or longer lasting loss of consciousness. If the stroke is severe, the affected person may not wake up in the morning or after a nap, despite someone trying to wake them.

Other potential symptoms might include: 5

• Tinnitus, a ringing in the ears, that will either be new and sudden or, if already regularly experienced, more severe than usual
• Vertigo, particularly when stroke affects the brain stem
• Nausea and vomiting
• Unusual breathing patterns
• Sudden sleepiness or difficulty waking up.

There is some evidence that women are more likely than men to experience certain symptoms during an ischemic stroke. These symptoms include: 6 7 8

• Pain
• Headaches
• Disorientation
• Weakness all over the body
• Loss of consciousness.

These symptoms may be more likely to be seen in women. However, many men may also experience these symptoms during stroke.

Certain symptoms are thought to be slightly more likely to be experienced by men than by women during ischemic stroke. These include:

• A lack of balance
• A burning or prickling sensation in the hands and feet
• Double vision
• Weakness on one side of the body.

However, many women may also experience these symptoms during a stroke.

There are two types of stroke - ischemic and hemorrhagic. Hemorrhagic strokes are divided into intracerebral and subarachnoid hemorrhages.

Symptoms differ slightly across these different types of stroke. However, a doctor generally can not make a diagnosis without a brain scan such as a CT scan.

Ischemic strokes occur when the blood supply to part of the brain is cut off. This occurs when a blood vessel becomes clogged due to a blood clot, a fatty deposit or a mix of the two. The vast majority of strokes are ischemic.

Read more about Ischemic Stroke »

Intracerebral hemorrhage is a hemorrhagic stroke, where the bleeding takes place within the brain. The following are more likely to be experienced during an intracerebral hemorrhage than an ischemic stroke:

• Sudden headache
• Nausea and vomiting
• Changed mental states, such as finding it difficult to wake up or sudden sleepiness
• Sudden loss of consciousness.

Read more about intracerebral hemorrhages and hemorrhagic stroke »

When the bleeding does not take place inside the brain, but on the organ’s surface, it is known as a subarachnoid hemorrhage. The most common symptom of a subarachnoid hemorrhage is a sudden, explosive headache, known as a thunderclap headache. 5

There is often a phase of intense headache for days or weeks before the bleed, which may go unnoticed as an early warning sign of subarachnoid hemorrhage.

Read more about Subarachnoid Hemorrhage »

Q: Are the signs of stroke different to the signs of a heart attack?
A: While both heart attacks and strokes are medical emergencies, they tend to have different symptoms. As they are both life-threatening, call the emergency services immediately if either condition is suspected. The main sign of a heart attack or myocardial infarction is a feeling of tightness or pain in the chest that may radiate into the arm or the neck, or lower jaw. Other signs include:

• Discomfort in the upper body
• Panic and/or anxiety,
• Sudden cold sweats
• Shortness of breath

The F.A.S.T acronym can be used to recognize the early warning signs of stroke.