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Transient Ischemic Attacks (TIA)


The Manual's Editorial Staff

Reviewed/Revised Sep 2023
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What is a transient ischemic attack (TIA)?

A TIA is a short-term problem in your brain. It is caused by a lack of blood flow to part of your brain.

  • TIAs come on suddenly and go away in an hour or less

  • The causes and symptoms of TIAs are the same as for strokes but a TIA ends before your brain is damaged

  • You get different symptoms depending on what part of your brain was affected

  • You may have face numbness or drooping, arm or leg weakness, difficulty seeing, or trouble speaking

  • Symptoms often involve only one side of your body

  • Go to the emergency room right away if you have any sudden TIA symptoms, even if symptoms went away quickly

  • Medicines may help prevent a stroke or another TIA

What causes a TIA?

TIAs are caused by a lack of blood flow to part of your brain from a blocked blood vessel in your brain.

A blocked blood vessel can be caused by:

  • A blood clot that forms in an artery in your brain

  • A blood clot that forms in your heart or a blood vessel near your heart that breaks loose, moves through your bloodstream, and gets stuck in a blood vessel in your brain

  • A fat deposit (plaque) that breaks off the lining of one of your blood vessels and gets stuck in a blood vessel in your brain

Fat deposits in your blood vessels are called atherosclerosis Atherosclerosis In people with atherosclerosis, patchy deposits of fatty material (atheromas or atherosclerotic plaques) develop in the walls of medium-sized and large arteries, leading to reduced or blocked... read more Atherosclerosis (hardening of the arteries). Atherosclerosis in the two big blood vessels in your neck (the carotid arteries) can cause a TIA or stroke because these blood vessels are the main blood supply to the brain.

The major risk factors for TIAs are:

Other risk factors include:

What are the symptoms of a TIA?

Symptoms of a TIA develop suddenly. They are identical to the symptoms of a stroke but are temporary. They usually last 2 to 30 minutes and go away completely within 1 hour.

Many different symptoms can occur, depending on which part of your brain isn't getting enough blood:

  • Feeling weak or numb on one side of your face or body

  • Difficulty talking

  • Trouble understanding what people say

  • Confusion

  • Loss of coordination

  • Blind spots in your vision

How will my doctor know if I had a TIA?

Doctors will also do tests to find out what caused your TIA:

How do doctors treat a TIA?

You may not need treatment for the TIA itself, because it doesn't cause lasting problems. However, doctors will treat the problems that caused your TIA to decrease your chances of a stroke in the future. Doctors may:

If you had a TIA because of narrowing of a blood vessel in your neck, doctors may do surgery to open the blood vessel. Or they might put a small tube (stent) in the blood vessel to keep it open.

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