What is a transient ischaemic attack (TIA)?

A transient ischaemic attack (TIA) happens when the blood supply to your brain is blocked for a short time.

This temporary blockage in blood supply causes sudden symptoms, such as weakness or problems talking or seeing. These symptoms get better on their own, usually within an hour.

If the blood supply is blocked for longer, this can cause a stroke.

Having a TIA increases your risk of having a stroke. Your risk of having a stroke is highest in the hours and days after having a TIA. Getting treatment after a TIA can greatly reduce your risk of stroke.

What are the symptoms of a TIA?

The symptoms of a TIA are like those of a stroke. But, unlike a stroke, your symptoms will disappear within 24 hours, and often within 1 hour.

Symptoms come on suddenly, and will depend on which part of your brain is affected. You may notice:

• weakness or paralysis
• numbness
• tingling

These symptoms may affect your face, arm or leg, often on just one side.

You may also have problems with your vision or speech. Problems with vision can include:

• temporary loss of vision in one or both eyes, like a black curtain coming up or down
• double vision
• not being able to see to the left or right

Problems with speech can include:

• not being able to say what you're thinking
• using the wrong words
• slurred speech (your tongue might feel thick)

Other symptoms of TIA

Other symptoms of a TIA can include:

• difficulty swallowing
• dizziness or vertigo (a spinning sensation)
• loss of balance
• problems with coordination

What is the F.A.S.T test?

If you think you are having a stroke, use the 'F.A.S.T.' test to check for symptoms.

• Face — Check your face. Is your face drooping on one side?
• Arms — Can you lift both arms?
• Speech — Is your speech slurred? Do other people understand you?
• Time is critical — If you see any of these signs or suspect that you or someone else may be having a stroke, call triple zero (000) straight away and ask for an ambulance.

What causes a TIA?

A TIA happens due to a short-term blockage of the blood supply in your brain.

The blockage is often due to a blood clot. Blood clots can:

• travel from your heart to your brain
• form in the blood vessels to your brain that have a build-up of fatty deposits (known as atherosclerosis)

Risk factors for TIA

Your risk of having a TIA is increased as you get older or if you have a family history of TIA and stroke.

It is also higher if you have:

• high blood pressure
• high cholesterol
• diabetes
• atrial fibrillation
• heart valve disease
• blocked blood vessels in your neck (carotid stenosis)
• heart failure

Smoking, heavy use of alcohol and being overweight also increase your risk of TIA and stroke.

When should I see my doctor?

Never ignore symptoms of a TIA. Your stroke risk is highest in the hours and days after a TIA, even if your symptoms go away. Call triple zero (000) and ask for an ambulance, even if your symptoms disappear.

How is a TIA diagnosed?

Your doctor will ask about your symptoms and how long they have lasted. They will want to know if you've had these symptoms before. They will also ask you about your lifestyle, general health and family history.

Your doctor will do a physical examination, including checking your blood pressure. They may recommend tests, including:

• blood tests
• a CT scan or MRI scan of your brain
• tests to check your heart, such as an electrocardiogram (ECG)
• a scan to check the blood vessels in your neck

If there is no evidence of a stroke on your brain scan and your symptoms get better within 24 hours, your doctor can diagnose a TIA.

How is a TIA treated?

Immediate treatment of a TIA usually includes taking aspirin. You may also be given other medicines to prevent blood clots.

If you've had a TIA, your doctor will discuss treatments to reduce your risk of having another TIA or a stroke. They may suggest lifestyle measures and medicines to reduce some of these risks.

You must not drive for at least 2 weeks after experiencing a TIA.

Lifestyle measures

Your doctor may recommend some lifestyle changes to reduce your risk of stroke. These may include:

• healthy eating
• getting enough physical activity
• maintaining a healthy weight
• quitting smoking and vaping
• avoiding alcohol

Medicines

Your doctor may prescribe medicines to:

• lower your risk of blood clots (blood thinners)
• control your blood pressure
• lower your blood cholesterol

Other treatments

Your doctor might recommend surgery if tests show that you have severe narrowing of the carotid arteries in your neck (carotid stenosis). This can improve the blood supply to your brain and lower your risk of stroke.

Your doctor will also treat any underlying conditions that can increase your risk of stroke, including:

• diabetes
• atrial fibrillation
• obesity
• heart failure
• obstructive sleep apnoea

What are the complications of TIA?

After having a TIA, you are at increased risk of having a stroke.

Your risk of having a heart attack is also increased.

Can a TIA be prevented?

There are things you can do to reduce your risk of having a TIA or stroke:

• Keep physically active.
• Eat a healthy diet with plenty of fruit and vegetables, whole grains, lean meats, poultry and fish, and reduced-fat dairy; limit your intake of salt, sugar and saturated fats.
• Maintain a healthy weight.
• If you smoke or vape, quit.
• Reduce the amount of alcohol you drink.

It's also important to make sure any other health problems you have are well treated. This includes:

• atrial fibrillation
• high blood pressure
• high cholesterol
• diabetes

Resources and support

Visit the Stroke Foundation website or call the StrokeLine on 1800 787 653. The Stroke Foundation has published a booklet on TIA.

The Stroke Foundation also has stroke information in languages other than English.

The Brain Foundation has information on TIA and other conditions that affect the brain.

You can also call the healthdirect helpline on 1800 022 222 (known as NURSE-ON-CALL in Victoria). A registered nurse is available to speak with 24 hours a day, 7 days a week.