Condition Basics

What is a transient ischemic attack (TIA)?

A transient ischemic attack (TIA) is an event that happens when blood flow to part of the brain is blocked or reduced, often by a blood clot. After a short time, blood flows again and symptoms go away. Symptoms are the same as a stroke but don't last long and don't cause lasting damage.

What causes it?

A TIA occurs when the blood supply to part of the brain is blocked for a short time. This may be caused by a blood clot. A clot may form in damaged blood vessels. A blood clot can also travel to the brain from another location, like the heart.

What are the symptoms?

A TIA can cause many different symptoms. They include sudden numbness, tingling, weakness, and loss of movement in a part of your body. A sudden, severe headache that is different from past headaches. Other symptoms include sudden confusion, vision changes, trouble speaking, fainting, seizure, and trouble walking or balancing.

How is it diagnosed?

Your doctor asks you about your medical history and does a physical examination. You may have tests, like a CT scan of the head or an MRI. These tests check for damage to the brain and other diseases. Other tests are often done to find the cause of the TIA.

How is a TIA treated?

Treatment for TIA is focused on preventing a stroke. A heart-healthy lifestyle and medicine can help. You may take medicine to prevent blood clots, lower blood pressure, lower cholesterol, and manage other health problems. Some people have surgery or a procedure to widen narrowed carotid arteries that supply blood to the brain.

Cause

A TIA occurs when the blood supply to part of the brain is reduced or blocked for a short time. This may be caused by a blood clot in a blood vessel. A clot may form in blood vessels that have a buildup of a substance called plaque. This buildup is called hardening of the arteries or atherosclerosis. A blood clot can also travel to the brain from another location, such as the heart or blood vessels in the neck.

Brain cells are affected within seconds of the blockage. This causes symptoms in the parts of the body that are controlled by those cells.

Sometimes a TIA is caused by a sharp drop in blood pressure that reduces blood flow to the brain. This is called a "low-flow" TIA. It is not as common as other types.

What Increases Your Risk

A risk factor is anything that makes you more likely to have a particular health problem. Some of the risk factors for a TIA are things you can manage or change.^{footnote 1} These include:

• Having a health problem such as atrial fibrillation, diabetes, high blood pressure, and high cholesterol.
• Smoking.
• Drinking too much alcohol. Your risk of harm from alcohol is low if you have 2 or less drinks per week, moderate if you have 3 to 6 drinks per week, and high if you have 7 or more drinks per week.
• Using recreational drugs. Recreational drugs include cocaine, amphetamines, and cannabis.
• Being overweight.
• Not eating healthy foods.
• Physical inactivity.

Risk factors you can't change include:

• Having had a previous TIA or stroke.
• Having a family history of TIA or stroke. Your risk is greater if a parent, brother, or sister has had a stroke or TIA.
• Being older. The risk of TIA increases with age.
• Being of Indigenous, African, or South Asian descent.
• Being female.
• Having certain problems during pregnancy, such as preeclampsia.
• Having gone through menopause.

Prevention

Here are some ways to reduce your risk of having another TIA and a stroke.

• Work with your doctor to manage other health problems, including atrial fibrillation, diabetes, high blood pressure, and high cholesterol.
• Take your medicine exactly as prescribed.
• Have a heart-healthy lifestyle.
  • Do not smoke or allow others to smoke around you. If you need help quitting, talk to your doctor.
  • Limit alcohol to 2 drinks or less per week. Work with your doctor to find what is right for you.
  • Stay at a healthy weight. Lose weight if you need to.
  • Be active. Ask your doctor what type and level of activity are safe for you.
  • Eat heart-healthy foods. These include vegetables, fruits, nuts, beans, lean meat, fish, and whole grains. Limit sodium and sugar.
  • If you think you may have a problem with alcohol or drug use, talk to your doctor.
• Get vaccinated against COVID-19, influenza (flu), and pneumonia.

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Symptoms

Symptoms of a TIA are the same as symptoms of a stroke. But symptoms of a TIA don't last very long. They may go away in a few minutes.

If you have any of these symptoms, call 9-1-1 or other emergency services right away.

Symptoms include:

• Sudden numbness, tingling, weakness, or loss of movement in your face, arm, or leg, especially on only one side of your body.
• Sudden vision changes.
• Sudden trouble speaking.
• Sudden confusion or trouble understanding simple statements.
• Sudden problems with walking or balance.
• Sudden, severe headache that is different from past headaches.

Ask your family, friends, and co-workers to learn the signs of a TIA and stroke. They may notice these signs before you do. Make sure they know to call 9-1-1 if these signs appear.

What Happens

A TIA doesn't cause lasting problems. But it is a serious warning sign of a possible stroke in the future. You can do a lot to lower your chance of having a stroke.

You and your doctor can work together to decide how to lower your risk of stroke. Medicines and a heart-healthy lifestyle can help.

When to Call a Doctor

Call 9-1-1 or other emergency services immediately if you have signs of a stroke, such as:

• Sudden numbness, tingling, weakness, or loss of movement in your face, arm, or leg, especially on only one side of your body
• Sudden vision changes
• Sudden trouble speaking
• Sudden confusion or trouble understanding simple statements
• Sudden problems with walking or balance
• Sudden, severe headache that is different from past headaches

Call your doctor now if you have:

• Any signs of bleeding and you are taking aspirin or other medicines that prevent blood clotting.

Call your doctor today if you think you have had a TIA in the past and have not yet talked with your doctor about your symptoms.

Examinations and Tests

You need to be checked by a doctor right away if you have had or are having a TIA. Your doctor will ask you about your medical history and do a physical examination. The examination results may be normal if the symptoms have already gone away.

If a TIA is suspected, the doctor may want to do tests. The tests include a CT scan of the head or an MRI to check for brain damage and look for diseases.

More tests are often done to find the cause of the TIA. Tests may include:

• An electrocardiogram (ECG, EKG) to check for heart rhythm problems that can lead to blood clots.
• An echocardiogram (echo) to look for clots or heart problems.
• Tests that check for narrowing or blockage in blood vessels of the neck, such as an ultrasound.
• Certain blood tests.

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Treatment Overview

If you've had a TIA, you need to see a doctor right away. After a TIA, you are at risk for a stroke. So you may stay in the hospital. You may have more tests and treatment.

Treatment for TIA is focused on preventing a stroke. A heart-healthy lifestyle and medicine can help. This lifestyle includes eating healthy, being active, staying at a healthy weight, and not smoking. You may take medicine to prevent blood clots, lower blood pressure, lower cholesterol, and manage other health problems. Some people have surgery or a procedure to widen narrowed carotid arteries that supply blood to the brain.

Self-Care

Medicines

• Be safe with medicines. Take your medicines exactly as prescribed. Call your doctor or nurse advice line if you think you are having a problem with your medicine.
• If you take a blood thinner, such as aspirin, be sure you get instructions about how to take your medicine safely. Blood thinners can cause serious bleeding problems.
• Call your doctor or nurse advice line if you are not able to take your medicines for any reason.
• Do not take any over-the-counter medicines or natural health products without talking to your doctor first.
• If you use hormonal birth control or hormone therapy for menopause, talk to your doctor. Ask if these are right for you. They may raise the risk of stroke in some people.

Heart-healthy lifestyle

• Do not smoke. If you need help quitting, talk to your doctor about stop-smoking programs and medicines.
• Be active. If your doctor recommends it, get more exercise. Walking is a good choice. Bit by bit, increase the amount you walk every day. You also may want to swim, bike, or do other activities. Try to do at least 2½ hours of moderate activity each week. It is fine to be active in blocks of 10 minutes or more throughout your day and week.
• Eat heart-healthy foods. These include vegetables, fruits, nuts, beans, lean meat, fish, and whole grains. Limit sodium and sugar.
• Stay at a healthy weight. Lose weight if you need to.
• Limit alcohol. Ask your doctor how much, if any, is safe for you.

Staying healthy

• Manage other health problems that raise your risk of stroke. These include atrial fibrillation, diabetes, high blood pressure, and high cholesterol.
• If you think you may have a problem with alcohol or drug use, talk to your doctor.
• Avoid infections such as COVID-19, colds, and influenza (flu). Get the flu vaccine every year. Get a pneumococcal vaccine shot. If you have had one before, ask your doctor whether you need another dose. Stay up to date on your COVID-19 vaccines.

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Medicines

Your doctor will probably prescribe several medicines after you've had a TIA. The medicines can help lower your risk of another TIA and a stroke.

Medicines to prevent blood clots are often used. This is because blood clots can cause TIAs and strokes. The types of medicines that prevent clotting are antiplatelets and anticoagulants.

Medicines to lower cholesterol and blood pressure are also used to prevent TIAs and strokes.

Medicines that prevent blood clots

Antiplatelet medicines keep platelets in the blood from sticking together. They include:

• Aspirin.
• Aspirin combined with dipyridamole.
• Other antiplatelet medicines, such as clopidogrel.

Anticoagulants prevent blood clots from forming. And they keep existing blood clots from getting bigger. Examples include:

• Direct oral anticoagulants.
• Warfarin.

You may take this type of medicine if you have atrial fibrillation or another condition that makes you more likely to have a stroke.

Cholesterol medicines

Cholesterol medicines lower cholesterol and the risk for a TIA or stroke. Examples are:

• Statins.
• Cholesterol absorption inhibitors.
• PCSK9-inhibitors.

Blood pressure medicines

Blood pressure medicines lower blood pressure and the risk for a TIA or stroke. Blood pressure medicines include:

• Angiotensin II receptor blockers (ARBs).
• Angiotensin-converting enzyme (ACE) inhibitors.
• Diuretics.

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Surgery

If you have serious blockage in the carotid arteries in your neck, you may choose to have a procedure to open the narrowed arteries. This can improve blood flow and help prevent a stroke.

During a surgical procedure, called carotid endarterectomy, a surgeon removes plaque buildup in the carotid arteries. During a catheter procedure, called carotid artery stenting, a thin tube is used to widen the narrowed artery and place a stent inside. The stent helps keep the artery open.

When a procedure is being considered after a TIA, the benefits and risks must be carefully weighed because the procedures may cause a stroke. Factors in the decision about having a procedure include your age, prior overall health, and current condition.

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