Condition Basics
What is a transient ischemic attack (TIA)?
A transient ischemic attack (TIA) is the mildest form of a stroke. It 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 typically don't cause lasting damage.
What causes it?
A TIA happens when there's a blockage in a blood vessel that supplies blood to part of the brain. The blockage can form when blood vessels are damaged by high blood pressure or high cholesterol. A blood clot can also travel to the brain from another location, like the heart or blood vessels in the neck.
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. Other symptoms include sudden confusion, vision changes, trouble speaking, fainting, seizure, and trouble walking or balancing.
Symptoms of a TIA are the same as a stroke. The most common symptoms are:
- Weakness or loss of power (sometimes described as numbness) in the face or an arm or leg.
- Loss of vision on one side.
- Trouble speaking or understanding speech, which can make people appear confused.
Other symptoms are:
- Tingling or “pins and needles” or loss of sensation on one side of the body.
- Loss of balance or coordination, including loss of walking balance.
- Nausea or headache may occur as well.
Symptoms usually last for 10 to 20 minutes.
How is it diagnosed?
Because TIA lasts only a short time (it’s transient), you are recovered from TIA by the time you see a doctor.
Your doctor will ask you about your medical history and does a physical examination. You may have tests, like a CT scan of the head or an MRI scan of your head and brain arteries. These tests check for damage to the brain and other diseases that might act like a TIA. Other tests are often done to find the cause of the TIA.
How is a TIA treated?
A TIA may happen before a more severe or permanent stroke. If you've had a TIA, your doctor will start you on medicines to help prevent a stroke. If tests show that the blood vessels (carotid arteries) in your neck are too narrow, you may need a procedure to open them up. This can help prevent blood clots that block blood flow to your brain.
Cause
A TIA happens when there is a blockage in a blood vessel that supplies blood flow to part of the brain. The blockage can form when blood vessels are damaged by high blood pressure or high cholesterol. 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 (modifiable risk factors).footnote 1 These include:
- Having a health problem such as high blood pressure (hypertension), atrial fibrillation, diabetes, or high cholesterol.
- Smoking.
- Drinking too much alcohol.
- Being overweight.
- Physical inactivity.
- Choosing a healthy diet.
Some of the risk factors are things you can't change (non-modifiable) include:
- Being older. The risk of TIA increases with age.
- Your genetics or family history. Your risk is greater if a parent, brother, or sister has had a stroke or TIA.
- Your sex. Risks are different for men and women.
- Your past medical history. Having had a previous TIA or stroke means you have a higher risk of these problems in the future.
Prevention
Here are some ways to reduce your risk of having another TIA and a stroke.
- Work with your doctor to manage any health problems that raise your risk. These health problems include 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 3 drinks a day for men and 2 drinks a day for women.
- 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.
Learn more
Watch
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 911 or other emergency services right away. If you continue to have symptoms, you are having a stroke and need medical attention now. If your symptoms go away in minutes, you have had a TIA and should see a doctor the same day.
Symptoms include:
- Sudden numbness, tingling, weakness, or loss of movement in your face, arm, or leg, especially on only one side of your body. Some people describe weakness or loss of power as numbness or “My arm went dead or limp.”
- Sudden loss or change of vision on one side.
- Sudden trouble speaking or understanding speech or writing.
Other symptoms are:
- Sudden tingling or “pins and needles” or loss of sensation in your face, arm, or leg, on only one side of the body.
- Sudden problems with coordination or balance, including loss of walking balance.
- Headache or nausea.
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 911 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.
Watch
When to Call a Doctor
Call 911 or other emergency services immediately if you have signs of a stroke, such as:
- Sudden weakness, or loss of movement in your face, arm, or leg, on only one side of your body. Some people describe weakness or loss of power as numbness or “My arm went dead or limp.”
- Sudden loss or change of vision on one side.
- Sudden trouble speaking or understanding speech or writing.
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 the same day 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 other diseases that might act like a TIA or stroke.
More tests are often done to find the cause of the TIA. Tests may include:
- A CT scan or magnetic resonance (MR) angiogram to look at the blood vessels that supply blood to the brain.
- An ultrasound of the carotid arteries to look at the blood vessels in the neck.
- A formal detailed angiogram (digital subtraction angiography) of the brain arteries.
- An electrocardiogram (ECG, EKG), Holter monitor, or longer-term heart rhythm monitor to check for heart rhythm problems that can lead to blood clots.
- An echocardiogram (echo) to look at heart function, the heart valves, or other heart problems.
- Certain blood tests to look for other health conditions that may put you at risk of stroke.
Learn more
Watch
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, 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.
- Get the influenza (flu) vaccine every year.
Learn more
Watch
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 (Aggrenox).
- Other antiplatelet medicines, such as clopidogrel (Plavix) and ticagrelor (Brillinta).
Anticoagulants prevent blood clots from forming. And they keep existing blood clots from getting bigger. Examples include:
- Direct oral anticoagulants, such as, apixaban (Elliquis), edoxaban (Lixiana), rivaroxaban (Xarelto), and dabigatran (Pradaxa).
- Warfarin (Coumadin).
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, such as atorvastatin (Lipitor) or rosuvastatin (Crestor).
- Cholesterol absorption inhibitor, such as ezetimibe (Ezetrol).
- 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.
Learn more
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.
Carotid artery angioplasty and stenting are sometimes done instead of surgery to prevent a TIA or stroke. It's also called carotid angioplasty and stenting. A doctor uses a thin tube called a catheter. The tube is put into an artery in your groin. It is threaded up to the carotid artery in your neck. The doctor then uses a tiny balloon to enlarge the narrowed part of the artery and places a metal stent to 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.
Learn more
Watch
References
Citations
- Gladstone DJ, et al. (2021). Canadian Stroke Best Practices, 7th ed. https://heartstrokeprod.azureedge.net/-/media/1-stroke-best-practices/secondary-prevention-of-stroke/csbpr7-spos-module-final-eng-2020.ashx?rev=0a12dfbc421a44369e8a2c2cf571c81e. Accessed November 30, 2021.
Credits
Adaptation Date: 8/3/2022
Adapted By: Alberta Health Services
Adaptation Reviewed By: Alberta Health Services