TIA (transient ischaemic attack)
Stroke symptoms that have fully resolved are still an emergency. Aspirin 300 mg now, specialist review within 24 hours, carotid imaging, and secondary prevention before the stroke happens.
A 64-year-old man with hypertension and diabetes says that yesterday his right hand went weak and his speech was slurred for about 20 minutes. It got completely better. He feels fine now and has come only because his daughter insisted. Examination is normal. BP 168/96, pulse irregular.
He looks well. Can he go home with a follow-up appointment next month?
- Is it still there?Any symptoms now: this is a stroke, not a TIA. Follow the Stroke pathway.
- Check the blood sugarLow sugar can cause brief stroke-like symptoms.
- Aspirin 300 mg nowUnless bleeding disorder, already on an anticoagulant, or true allergy.
- ECG and pulseAF is a common and treatable cause.
- Refer for specialist reviewWithin 24 hours if the TIA was in the last 7 days.
- On an anticoagulant?Admit for urgent CT head to exclude bleeding before anything else.
- Carotid DopplerFor anterior circulation symptoms, in anyone who could have surgery.
- Start preventionStatin, BP control, stop smoking, anticoagulation for AF once bleeding is excluded.
- Symptoms still present, or come back
- Two or more TIAs in a week (crescendo TIA)
- On warfarin or a DOAC
- AF
- Sudden loss of vision in one eye
- Severe headache with the episode
- A stroke that has not fully resolved
- Low blood sugar
- Brain haemorrhage in a patient on anticoagulants
- AF
- Severe carotid stenosis
- Giant cell arteritis causing loss of vision
| TIA | Sudden focal symptoms that resolve completely, usually within an hour |
| Aspirin | 300 mg now, then daily until specialist review |
| Referral | Within 24 hours if within the last 7 days. Within 7 days if longer ago |
| ABCD2 score | Not used to decide urgency. Every suspected TIA is urgent |
| Carotid narrowing 50–99% on the symptomatic side | Refer urgently for carotid surgery |
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On this page
Why a TIA is an emergency
A TIA is a brief episode of stroke symptoms caused by a temporary blockage of blood flow, with complete recovery and no infarct on imaging. Symptoms usually last minutes, rarely more than an hour.
The patient often looks completely well. That is the trap. The risk of a stroke is highest in the first 48 hours and the first week. Fast assessment and treatment prevent many of these strokes.
- Day 0TIA: symptoms resolve
- First 48 hHighest stroke risk
- First weekRisk still high
- Weeks laterRisk falls with treatment
Is it a TIA?
- Weakness or numbness of the face, arm or leg on one side.
- Difficulty speaking or understanding speech.
- Loss of vision in one eye (amaurosis fugax: "a curtain came down") or half the visual field.
- Double vision, unsteadiness or vertigo with other brainstem signs.
- Isolated dizziness, light-headedness or vertigo on its own.
- Fainting or blackout (loss of consciousness is rarely a TIA).
- Confusion alone, or memory loss alone (transient global amnesia).
- Symptoms that spread slowly over minutes (migraine aura) or march from one body part to another.
- Tingling around the mouth and both hands (anxiety and over-breathing).
| Mimic | Clues |
|---|---|
| Migraine aura | Spreading symptoms over minutes, flashing lights or zigzags, followed by headache, previous similar episodes |
| Focal seizure and Todd's paresis | Jerking first, then weakness |
| Low blood sugar | On insulin or a sulfonylurea, sweaty |
| Syncope | Light-headed, pale, brief loss of consciousness, no focal signs |
| Inner ear (vestibular) problems | Vertigo with head movement, no other neurological signs |
| Subdural haematoma | Older, falls, blood thinners, fluctuating symptoms |
| Brain tumour | Recurrent identical episodes, headache, gradual progression |
History and examination
- Exactly what happened: which side, which body parts, speech, vision; how it started; how long it lasted; how it ended.
- Repeated episodes? Two or more in a week (crescendo TIA) means very high risk.
- Risk factors: hypertension, diabetes, smoking, cholesterol, AF, previous stroke, heart valve disease.
- Medicines: especially anticoagulants and antiplatelets.
- Headache, jaw pain on chewing, scalp tenderness in someone over 50 with loss of vision: think giant cell arteritis and check ESR and CRP the same day.
- Examine: full neurological examination (should now be normal), pulse rhythm, BP, heart murmurs, carotid bruit, fundi.
What to do now
- Still symptomatic?Treat as stroke. Do not call it a TIA until it has fully resolved.
- Sugar and ECGExclude low sugar. Look for AF.
- Aspirin 300 mgNow, unless contraindicated or on an anticoagulant.
- On an anticoagulant or bleeding disorder?Admit for an urgent CT head to exclude a bleed. No aspirin until the CT is done.
- Arrange specialist reviewWithin 24 hours if the TIA was in the last 7 days.
- Arrange testsCarotid Doppler, ECG monitoring, bloods, brain imaging as advised.
- Start preventionStatin, BP plan, stop smoking.
- Explain the warning signsReturn immediately if symptoms come back. Do not drive.
Who to admit
- Symptoms still present or recurring
- Two or more TIAs in a week (crescendo)
- On an anticoagulant or bleeding disorder
- New AF
- Cannot get specialist review and tests within 24–48 hours
- Fully recovered single episode
- Aspirin started
- Tests arranged
- Clear warning-sign advice
Many hospitals in Pakistan have no rapid-access TIA clinic. Do not book the patient into a routine clinic weeks away. Discuss with the medical or neurology team the same day, arrange the carotid Doppler, ECG, bloods and imaging within a day or two, and admit if this cannot happen. The aim is that the patient is fully assessed and on treatment within 24–48 hours.
Do not use the ABCD2 score
The ABCD2 score (age, BP, clinical features, duration, diabetes) was once used to decide how urgently to see TIA patients. It is no longer recommended for this, because it misses high-risk patients (for example those with AF or carotid stenosis). Treat every suspected TIA as urgent.
Investigations
| Test | Why | What it changes |
|---|---|---|
| ECG, and longer monitoring if needed | AF, which may come and go | Anticoagulation instead of antiplatelets |
| Carotid Doppler (or CT angiogram) | Narrowing of the internal carotid artery | 50–99% narrowing on the symptomatic side: urgent carotid surgery |
| MRI with diffusion imaging | Confirms a small infarct, or finds another cause | Decided by the specialist |
| CT head | Urgently if on anticoagulants or bleeding disorder | Excludes haemorrhage |
| CBC, sugar, HbA1c, lipids, creatinine, electrolytes | Risk factors and baseline | |
| ESR, CRP | Over 50 with visual loss or headache | Giant cell arteritis needs steroids the same day |
| Echo | Suspected heart source (murmur, young patient) | Valve disease, clot, hole in the heart |
Carotid surgery
Patients with a 50–99% narrowing of the internal carotid artery on the same side as their symptoms benefit from carotid endarterectomy. The benefit is greatest when surgery happens early, ideally within 2 weeks of the TIA. Refer urgently to the vascular surgeons once the Doppler result is known.
Antiplatelets and anticoagulation
- Most patients: aspirin 300 mg until reviewed. Long term, clopidogrel 75 mg daily is commonly used.
- Dual antiplatelets: for a high-risk TIA or minor stroke seen early, specialists often give aspirin plus clopidogrel (with loading doses) for 21 days, then clopidogrel alone. This is a specialist decision. Do not start it yourself.
- AF: anticoagulation (usually a DOAC) is better than aspirin. After a TIA it can usually start as soon as a brain bleed has been excluded. Discuss with your senior.
- Rheumatic mitral stenosis or a metal valve: warfarin. See Atrial fibrillation.
Long-term prevention
- BP: target usually below 130/80 once reviewed.
- Statin: atorvastatin, aiming for a large fall in LDL cholesterol.
- Diabetes control, stop smoking (including huqqa and naswar), exercise, less salt, healthy weight.
- Driving: no driving until reviewed. Usually at least 1 month after a TIA. Follow local rules.
Common mistakes
- Reassuring a patient who "looks fine" and booking a routine clinic.
- Using the ABCD2 score to decide that a TIA is "low risk".
- Giving aspirin to a patient on warfarin or a DOAC before a CT.
- Missing AF because the pulse was not felt or no ECG was done.
- Calling isolated dizziness or a faint a TIA.
- Missing giant cell arteritis in an older patient with sudden loss of vision.
Frequently asked questions
What is the treatment for a TIA?
Aspirin 300 mg immediately (unless contraindicated or on an anticoagulant), specialist review within 24 hours, carotid imaging, ECG for AF, a statin and BP control. Patients on anticoagulants need an urgent CT head first.
How urgently should a TIA be seen?
Within 24 hours by a specialist if the TIA was in the last 7 days, and within 7 days if it was longer ago. Every suspected TIA is treated as urgent.
Is the ABCD2 score still used?
Not to decide urgency. Guidelines now recommend treating every suspected TIA urgently, because ABCD2 misses some high-risk patients.
When is carotid endarterectomy recommended after a TIA?
When there is 50–99% narrowing of the internal carotid artery on the side that caused the symptoms. Surgery should be done as early as possible, ideally within 2 weeks.
What is amaurosis fugax?
Sudden temporary loss of vision in one eye, often described as a curtain coming down. It is a TIA affecting the eye and is managed with the same urgency.
Test yourself
Exam-style questions on this guide, from our two question banks. Choose an answer to see why each option is right or wrong.
1. A 64-year-old man had 20 minutes of right hand weakness and slurred speech yesterday, now fully resolved. Pulse is irregularly irregular. CT head shows no bleed. Which long-term treatment is most likely once AF is confirmed?
Answer: Anticoagulation. TIA with AF: once bleeding is excluded, anticoagulation (usually a DOAC) is the secondary prevention. Specialist review within 24 hours.
- Carotid endarterectomy alone: AF is the likely embolic source here.
- Clopidogrel long term: Antiplatelets are less effective than anticoagulation in AF.
- Aspirin long term: In AF, anticoagulation replaces aspirin for stroke prevention.
- No treatment as symptoms resolved: TIA carries a high early stroke risk.
2. A 70-year-old woman had a TIA this morning. She takes apixaban for AF. What is the best next step?
Answer: Urgent CT head, no aspirin. TIA in a patient already anticoagulated needs urgent imaging to exclude haemorrhage and specialist review.
- Aspirin 300 mg now: Adds bleeding risk in an anticoagulated patient and a bleed has not been excluded.
- Stop apixaban and start aspirin: Not appropriate without specialist advice.
- Double the apixaban dose: No role.
- Discharge with outpatient review: TIA on anticoagulation needs urgent assessment.
3. A carotid Doppler after a TIA shows 75% stenosis of the internal carotid artery on the symptomatic side. What is the best management?
Answer: Carotid endarterectomy. Symptomatic carotid stenosis of 50–99% (NASCET) benefits most from endarterectomy within 2 weeks of the event.
- No action until a second TIA: Delay increases stroke risk.
- Aspirin only and recheck in a year: Symptomatic significant stenosis benefits from early surgery.
- Warfarin: Not the treatment for carotid stenosis.
- Carotid stenting for all: Endarterectomy is the usual choice.
4. A 68-year-old smoker describes a ‘curtain’ coming down over his right eye for 3 minutes, then full recovery. Fundoscopy shows a bright refractile plaque at a retinal arteriolar bifurcation. What is the next investigation?
Answer: Carotid Doppler ultrasound. Amaurosis fugax: transient monocular visual loss from retinal emboli — usually from ipsilateral carotid atheroma (Hollenhorst cholesterol plaques) or cardiac source; a retinal TIA. Urgent stroke work-up: carotid Doppler (endarterectomy if 50–99% symptomatic stenosis), ECG/Holter, echo, BP, lipids, glucose; antiplatelet and statin. Consider GCA in older patients.
- MRI orbit: MRI orbit is not first.
- Fluorescein angiography: Fluorescein angiography is not first.
- Visual field test only: A field test alone misses the embolic source.
5. A 68-year-old had 20 minutes of left arm weakness that fully resolved. He is in AF and not anticoagulated. What is the key secondary prevention?
Answer: Anticoagulation (DOAC). TIA is transient neurological dysfunction without infarction; it carries a high early stroke risk. All need urgent specialist assessment within 24 h, antiplatelet loading (unless cardioembolic), brain and vascular imaging, ECG/Holter. In AF, anticoagulation is the key prevention. Carotid endarterectomy for symptomatic stenosis 50–99% (ideally within 2 weeks). Statin and BP control for all.
- Aspirin alone: Aspirin is inferior to anticoagulation in AF.
- Carotid endarterectomy: The source is cardioembolic, not carotid.
- Reassurance only: The early stroke risk is high.
6. Why does a single dose of aspirin inhibit platelet function for about 7–10 days?
Answer: Irreversible COX-1 acetylation. Aspirin irreversibly acetylates cyclooxygenase-1 (serine 529), blocking thromboxane A₂ synthesis in platelets. Anucleate platelets cannot synthesise new COX, so the effect lasts for the platelet lifespan (7–10 days) even though aspirin has a half-life of minutes. Endothelial cells regenerate COX and keep making prostacyclin (PGI₂), a vasodilator and platelet inhibitor; low doses favour this balance. Stop aspirin about 7 days before surgery if bleeding risk is high.
- Permanent P2Y12 block: That is clopidogrel, ticagrelor (reversible) or prasugrel.
- Irreversible fibrinogen binding: Not the mechanism.
- Blocks vitamin K epoxide reductase: That is warfarin.
- Very slow excretion: Its half-life is short.
7. A 65-year-old smoker has brief painless loss of vision in his right eye, 'like a curtain coming down', lasting 2 minutes. Which artery most likely carried the embolus to the retina?
Answer: Ophthalmic artery from the right ICA. Amaurosis fugax is transient monocular blindness from emboli, usually from an atheromatous plaque at the ipsilateral internal carotid bifurcation. The ophthalmic artery, the first major branch of the internal carotid, gives the central retinal artery. It counts as a TIA: carotid Doppler is needed, and significant symptomatic stenosis is treated with carotid endarterectomy.
- Right posterior cerebral artery: Occipital lobe loss affects both eyes' fields.
- Left middle cerebral artery: Wrong side and not the retina.
- Right vertebral artery: Posterior circulation, not one eye.
- Right facial artery: External carotid branch, supplies the face.
References and dose sources
- NICE NG128: Stroke and TIA in over 16s, diagnosis and initial management
- National Clinical Guideline for Stroke for the UK and Ireland (2023)
- Aspirin dosing: Drugs.com: Aspirin dosage (see also our aspirin dose page)
- Atorvastatin dosing: Drugs.com: Atorvastatin dosage (see also our atorvastatin dose page)
International guidance is linked where it reflects good practice. Where your hospital’s protocol differs, follow your hospital.