REASONING GP · Clinical algorithm · Quick reference

Dizziness in adults — triage and diagnostic approach

Daytime GP and OOH/111 face-to-face or remote. Decide which of the four complaints this is, screen the brain and the heart, then name the syndrome. Ongoing management of each diagnosis is in the full Steps pathway.
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AdultsGP + OOHDiagnosis firstv1.0 · Sep 2026
Core rule. "Dizzy" is four different complaints and the word is not a diagnosis. Ask first: does the room spin (vertigo), do you feel faint (presyncope), are you unsteady (disequilibrium), or is it vague wooziness? Then answer the two that kill: is this a posterior circulation stroke, and is this cardiac? Every patient needs a lying and standing BP and a pulse; every transient loss of consciousness needs a 12-lead ECG (CG109). Timing and triggers separate the causes better than how the patient describes it.
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Before any history: is this an emergency now? Stop the consultation and call 999 if any of these is present
New vertigo with any central sign — diplopia, dysarthria, dysphagia, facial or limb weakness, limb ataxia, new deafness, Horner's · unable to sit or walk unaided · direction-changing or vertical nystagmus · sudden severe headache or neck pain with the dizziness · GCS <15 or seizure · systolic BP <90, pulse >120 or <40, new irregular rhythm · syncope on exertion or lying down, or preceded by chest pain or palpitations · bleeding with postural collapse · glucose <4 mmol/L uncorrected. ABCDE, observations, ECG if it will not delay transfer, exact onset time, hand over.
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Define which complaint this is, and its timing Timing, triggers and targeted examination — not the adjective the patient chooses

Which of the four?

Vertigo — illusion of movement. Presyncope — about to faint, greying vision, clammy. Disequilibrium — unsteady only upright or walking. Light-headed — vague, often continuous. Ask which came first.

Timing

Seconds on head movement (BPPV) · minutes (TIA, presyncope, arrhythmia) · 20 min to hours with hearing change (Ménière's) · hours to days, continuous (neuritis, stroke) · weeks and progressive (central lesion, drug, PPPD) · only on standing (orthostatic).

Triggers

Rolling over or looking up (BPPV) · standing (orthostatic) · exertion (aortic stenosis, arrhythmia) · head turning, cough, micturition (vagal) · visual motion or busy places (PPPD, vestibular migraine) · post-viral (neuritis) · after neck trauma or manipulation (dissection).

Context

Age, frailty, falls · vascular risk, AF, structural heart disease, family history of sudden death under 40 · migraine · new or changed drugs (antihypertensives, nitrates, alpha-blockers, anticholinergics, opioids, gentamicin) · alcohol · anaemia, bleeding, dehydration, diabetes.
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Red-flag screen: trigger → concern → destination → what to do before handover One row is enough; do not add up reassuring features
Trigger / red flagLeading concern · destinationDo now · do not delay
Acute continuous vertigo with a central feature: any brainstem or cerebellar sign (diplopia, dysarthria, dysphagia, facial or limb weakness, limb ataxia), direction-changing or vertical nystagmus, skew deviation, a normal head-impulse test, inability to stand or walk unaided, new severe headache or neck pain, or vascular risk factors. Posterior circulation stroke · cerebellar infarct or haemorrhage
999 now		 A normal head impulse in acute continuous vertigo points to a central cause, not a reassuring one. HINTS+ applies only to continuous vertigo with nystagmus, examined by someone trained — never to positional vertigo and never remotely. Say "acute vestibular syndrome, query posterior stroke": CT misses about half of posterior strokes, so MRI is the test. Isolated vertigo can still be stroke; inability to walk unaided is the most useful single discriminator.
Vertigo with new unilateral hearing loss or tinnitus, especially with headache or neck pain, or after neck trauma or manipulation. AICA or labyrinthine infarct · vertebral artery dissection · sudden sensorineural hearing loss
999 if central signs or dissection Emergency ENT within 24 h for sudden SNHL		 Do not label new deafness with vertigo as labyrinthitis: sudden SNHL needs audiometry and steroids within days (NG98), and an AICA stroke produces the same picture. Test hearing with Weber and Rinne and document the side. Neck pain after trauma or manipulation is a dissection until excluded.
Syncope or presyncope with a cardiac marker: on exertion or supine · preceded by palpitations or chest pain · no prodrome · injury from the episode · murmur or heart failure · family history of sudden cardiac death under 40 · abnormal ECG (long or short QT, Brugada, delta wave, pathological Q waves, bifascicular block, bradycardia <40). Arrhythmia · aortic stenosis · hypertrophic cardiomyopathy · channelopathy
999 if ongoing arrhythmia, chest pain or injury Cardiology within 24 hours		 12-lead ECG in everyone with transient loss of consciousness (CG109); a normal ECG does not exclude arrhythmia, so the history still decides. Exertional syncope is aortic stenosis or HCM until an echo says otherwise. Advise no driving and no work at height or with machinery until assessed, and record it. Do not order an ambulatory monitor and review at a distance.
Postural dizziness with a cause for volume loss or shock: melaena, haematemesis, rectal or heavy menstrual bleeding · vomiting or diarrhoea · fever · new abdominal or back pain over 50 · pallor · pregnancy possible. GI bleed · sepsis · ruptured AAA · ectopic pregnancy · Addisonian crisis
999 if shocked Same-day acute assessment		 Lying and standing BP, pulse, temperature; same-day FBC and U&E; urine pregnancy test in every woman of reproductive age. A postural drop with a bleeding history is hypovolaemia, not orthostatic hypotension — do not just stop an antihypertensive and review. Back or abdominal pain with collapse over 50 is an AAA until excluded.
Progressive, sub-acute loss of central neurological function — worsening imbalance or gait ataxia over weeks with cognitive or personality change, progressive focal weakness, dysarthria, dysphagia or visual field loss. Brain or CNS tumour
Urgent direct-access MRI brain within 2 weeks — CT if MRI contraindicated · NICE NG12		 Refer on the urgent suspected-cancer route, stating the progressive deficit (NG12). Fundoscopy and full neurology first: papilloedema, a new seizure, reduced consciousness or rapid progression is a same-day admission, never a 2-week scan — as is new dizziness in cancer or immunosuppression. A normal scan with a progressing deficit still needs neurology. Asymmetric hearing loss with imbalance is a separate route: urgent ENT or audiology for MRI of the internal auditory meati (NG98).
Medication or toxin: new or up-titrated antihypertensive, nitrate, alpha-blocker, diuretic, antidepressant, antipsychotic, anticholinergic, opioid, antiepileptic or hypnotic · gentamicin or other aminoglycoside · alcohol or withdrawal · carbon monoxide (others at home unwell, better away from home). Drug-induced orthostatic hypotension · vestibulotoxicity · toxic cause
Same-day drug review, or acute assessment if CO or withdrawal		 Reconcile the drug list with start and dose-change dates against symptom onset — the commonest reversible cause in older patients. Aminoglycoside vestibulotoxicity is permanent: stop and seek specialist advice the same day. Suspected CO: remove from the source, 999 if symptomatic.
Recurrent falls or dizziness in a frail older adult, with polypharmacy, cognitive impairment, fracture risk, or a fall with head injury on an anticoagulant. Multifactorial falls syndrome · occult fracture · subdural haematoma
Same-day CT if anticoagulated head injury (NG232) Falls service		 Anticoagulant plus head injury is a same-day CT however well the patient looks. Otherwise lying and standing BP, ECG, medication review, gait assessment and the falls pathway (CG161). "Dizziness in the elderly" is usually several small causes together, each separately fixable.
Safety rule. A normal neurological examination, a normal CT, a young age, a previous episode or a convincing viral prodrome each lower probability; none excludes posterior circulation stroke or arrhythmia. If a row applies and the safe destination is unavailable, escalate rather than observe.
Colour is semantic: red = emergency now · amber = same-day acute assessment · blue = define/assess · green = primary-care diagnosis · purple = uncertain / specialist route (including 2WW). Continued on page 2: examination, classification, syndrome classifier, routine referral, primary-care treatment, endpoint.
REASONING GP · Dizziness in adults — triage and diagnostic approach
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Focused examination and investigation Remote assessment that cannot measure a postural BP or examine eyes and gait is an escalation criterion

Measure, always

Lying and standing BP — supine 5 min, then at 1 and 3 min standing; a fall of ≥20 systolic or ≥10 diastolic, or systolic below 90, is orthostatic hypotension. Pulse and rhythm, RR, SpO₂, temperature, glucose. 12-lead ECG after any loss of consciousness or cardiac marker (CG109).

Eyes and ears

Nystagmus: direction, whether it changes with gaze, vertical or torsional. Pursuit and saccades. Cover–uncover for skew deviation. Otoscopy both ears. Hearing: whispered voice, Weber and Rinne — document the side of any loss.

Positional and vestibular tests

Dix–Hallpike for posterior-canal BPPV: a few seconds' latency, up-beating torsional nystagmus, fatigues on repetition; supine roll test for horizontal canal. HINTS+ only in acute continuous vertigo with nystagmus, by a trained examiner.

Neurology, gait and tests

Cranial nerves, power, coordination, finger–nose, heel–shin, Romberg, and walking unaided. Same-day FBC, U&E, glucose; consider TFT, HbA1c, B12, ferritin, calcium. Not in primary care: CT for acute vertigo, or a vestibular sedative in place of a diagnosis.
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Classify: three exits, not two "Dizziness" and "labyrinthitis" are not diagnoses

Serious cause likely

Any red flag, central sign, cardiac marker, postural drop with volume loss, or progressive deficit. Output: name the concern, use the destination above, record BP, ECG, gait and onset.

Cause established, treatable in primary care

No red flags, normal neurology and gait, and timing and triggers fit one syndrome below with a positive confirming test. Output: syndrome, positive finding, treatment, driving advice, review date.

Unclassified / uncertain

Vague or mixed symptoms, normal examination with persisting disability, recurrent syncope with a normal ECG, or frailty with several contributors. Output: never "just her age" — state the uncertainty, the §6 route, and who reviews when.
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Syndrome classifier: timing and trigger, then the confirming test Only once the red-flag screen is negative
BPPVSeconds to under a minute, triggered by rolling over, lying down or looking up; no hearing loss; well between attacks. Positive Dix–Hallpike is the diagnosis — do the test rather than treating by description.
Vestibular neuritis / labyrinthitisContinuous vertigo over hours to days with nausea, worse on head movement, settling over days to weeks; often post-viral. Abnormal head impulse, unidirectional nystagmus, able to walk. Hearing loss makes it labyrinthitis — and mandates excluding sudden SNHL and AICA stroke first.
Ménière's diseaseAttacks of 20 minutes to 12 hours with fluctuating unilateral hearing loss, tinnitus and aural fullness. Needs audiometry and ENT confirmation. Progressive unilateral loss without vertigo is vestibular schwannoma until imaged.
Vestibular migraineRecurrent episodes of minutes to 72 hours with migraine features in someone with a migraine history; triggered by visual motion, sleep loss or hormones. The commonest cause of recurrent spontaneous vertigo, and routinely missed because the headache may be absent in the attack.
Orthostatic and vasovagal — the presyncope familyOrthostatic: dizziness within seconds to 3 minutes of standing, eased by sitting; confirmed by the postural BP above. Ask what is causing it — drugs, dehydration, bleeding, autonomic failure, adrenal insufficiency. Vasovagal: prodrome of warmth, nausea, sweating, tunnel vision; provoked by standing, pain, heat, emotion, cough or micturition; rapid recovery. A clear three-P history (posture, provoking factor, prodrome) with a normal ECG needs no cardiac referral (CG109).
PPPD, and what not to labelPersistent postural-perceptual dizziness: 3 months or more of non-spinning unsteadiness, worse standing, walking or in visually busy places, usually after an acute vestibular event, anxiety or panic; normal examination. A positive diagnosis with its own treatment, not a synonym for anxiety. Do not label by default: "labyrinthitis" for anything continuous (most are neuritis, some are stroke) · "cervical vertigo" without neck findings · "anxiety" while any measurement is abnormal · disequilibrium in frailty is real but is a list of fixable contributors — vision, neuropathy, drugs, strength.
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Refer routinely from this consultation Not same-day, not 999 — the cases that leave by letter; what follows in §7 is what primary care treats today
Asymmetric or progressive sensorineural hearing loss with imbalance → urgent ENT/audiology for MRI of the internal auditory meati (vestibular schwannoma, NG98) · suspected Ménière's → ENT with audiometry before long-term treatment · BPPV failing two Epley manoeuvres, or horizontal-canal BPPV → ENT or vestibular physiotherapy · neuritis beyond 6 weeks or PPPD → vestibular rehabilitation (SSRI in parallel for PPPD) · vestibular migraine uncontrolled after prophylaxis → neurology · unexplained recurrent syncope, normal ECG, no red flag → cardiology for ambulatory monitoring or tilt testing (CG109) · recurrent falls, or a fall with injury in frailty → multifactorial falls assessment (CG161).
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The only treatment decisions that belong in this consultation What primary care treats today
BPPV, positive Dix–HallpikeEpley manoeuvre at the same visit — effective in most patients after one or two attempts, and the definitive treatment. Vestibular sedatives do not treat BPPV and impair compensation: do not prescribe them for it. Teach Brandt–Daroff exercises and review at 4 weeks.
Acute vestibular neuritis, first daysProchlorperazine, cinnarizine or cyclizine for symptoms, short course only — stop within about 3 days, as longer use delays central compensation (NICE CKS). Buccal prochlorperazine if vomiting. Mobilise early. Betahistine has no role. Persisting at 6 weeks → section 6.
Orthostatic hypotensionTreat the cause: reduce or stop the culprit drug (highest yield), correct volume, treat bleeding or infection. Rise slowly in stages, adequate fluid and salt if not contraindicated, avoid large hot meals and alcohol, compression hosiery, head-up bed.
Ménière's, confirmedBetahistine for attack frequency, low-salt diet, avoid caffeine and alcohol; prochlorperazine for an acute attack only. Audiometry and ENT follow-up. Do not start long-term betahistine on an unconfirmed label.
Stroke, arrhythmia, sudden hearing loss, dissection, GI bleed, sepsisTransfer or the same-day route is the treatment. Do not give a vestibular sedative to a patient with central signs — it masks the picture and delays the scan. Do not start or stop an anticoagulant unilaterally. Do not treat new unilateral deafness with vertigo as labyrinthitis.
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Endpoint and documentation Finish with one of four conclusions

1 · Time-critical serious

999 route taken; suspected diagnosis, onset, central signs, whether the patient walks unaided, observations, ECG, glucose, drugs and times.

2 · Serious possible

Same-day acute, ENT or cardiology assessment arranged; the question being excluded, postural BP, ECG result, who was spoken to, deadline.

3 · Cause established

Syndrome with its positive test; treatment including any manoeuvre performed; drugs stopped; driving advice recorded; review date.

4 · Unclassified

Uncertainty stated; §6 referral or NG12 route sent, with date; interim safety advice; review owner and timeframe; escalation criteria.
Why a primary-care diagnosis is safe today, in one line: no row on the page-1 screen applies · postural BP, pulse and glucose recorded · ECG done where there was any loss of consciousness · neurology, gait and hearing normal and the patient walks unaided · timing and trigger fit one syndrome with a positive confirming test · drugs reconciled · written safety-net and a booked review. Driving — record it every time: Group 1 licence holders must not drive while liable to sudden and disabling dizziness or vertigo and must notify the DVLA if episodes are recurrent or unpredictable (Group 2 stricter); after a single unexplained syncope driving stops pending assessment. Safety-net wording: call 999 for weakness, numbness, slurred speech, double vision, severe headache or neck pain, inability to walk unaided, or fainting on exercise or lying down; same-day contact for new deafness or tinnitus in one ear, black stools, chest pain, palpitations, or dizziness worsening rather than settling.
OOH / remote limitation. Convert to face-to-face or emergency assessment if a lying and standing BP, pulse, glucose or ECG cannot be obtained; the eyes, gait and hearing cannot be examined; the vertigo is continuous and present during the call; there was a loss of consciousness; the patient cannot walk unaided or describes new deafness, headache or neck pain; or the patient is frail or anticoagulated.
Clinical decision support only; follow local emergency-transfer and referral policies and check doses against the current BNF. Source hierarchy: NICE guidelines and CKS first, then BNF/MHRA for doses and safety, then national specialty guidance. Sources: NICE CG109 Transient loss of consciousness · NG128 Stroke and TIA · NG98 Hearing loss in adults · NG232 Head injury · CG161 Falls in older people · NG12 Suspected cancer (May 2025) · NICE CKS Vertigo, BPPV, Ménière's disease, Blackouts and syncope · BNF · MHRA · Bárány Society criteria · DVLA Assessing fitness to drive. Review after any guidance or medicines-safety update, otherwise every 6 months. © Reasoning GP · gpreasoning.uk