Why Dizziness History Is Tested
Dizziness is one of the top five presenting complaints in primary care and A&E. It requires careful history taking to distinguish benign causes like BPPV from potentially life-threatening central pathology like posterior fossa stroke. OSCE stations often include red flag vignettes designed to catch students who jump to a peripheral diagnosis without asking the right questions.
Step 1: Define What the Patient Means by "Dizzy"
"Dizziness" means different things to different patients. Your first job is to clarify the type:
| Type | Patient description | Likely cause |
|---|---|---|
| True vertigo | "The room is spinning" or "I'm spinning" | Peripheral or central vestibular |
| Pre-syncope | "I feel like I'm going to faint", grey out | Cardiovascular, postural hypotension |
| Disequilibrium | "I feel unsteady on my feet" | Cerebellar, proprioceptive, peripheral neuropathy |
| Non-specific lightheadedness | "I feel floaty or woozy" | Anxiety, hyperventilation, anaemia |
💡 Tip
Ask: "Can you describe exactly what you feel when it happens? Does it feel like the world is spinning, or like you might faint?" This single question focuses the whole history.
Step 2: Characterise the Vertigo
Once you've confirmed true vertigo, explore it with SOCRATES:
Onset:
- "Did it come on suddenly or gradually?"
- Sudden onset suggests peripheral (BPPV, labyrinthitis) or central stroke
Duration of each episode:
- Seconds to a minute: strongly suggests BPPV
- Hours: suggests Meniere's disease
- Days: suggests vestibular neuritis or labyrinthitis
- Constant and worsening: central pathology until proven otherwise
Triggers:
- "Does turning over in bed or looking up make it worse?" (BPPV)
- "Does it come on with no particular trigger?" (central or vestibular neuritis)
- "Does it come on when you stand up?" (postural hypotension)
Associated symptoms:
- Hearing loss and tinnitus: Meniere's disease
- No hearing loss: BPPV or vestibular neuritis
- Nausea and vomiting: present in most vestibular causes
- Headache: consider posterior fossa pathology
- Falls: assess severity and functional impact
Peripheral vs Central Vertigo, Key Differences
| Feature | Peripheral | Central |
|---|---|---|
| Onset | Usually sudden | Sudden (vascular) or gradual (tumour) |
| Duration | Seconds (BPPV) to days | Days to weeks, or continuous |
| Nystagmus | Horizontal, fatigues | Vertical or direction-changing, does not fatigue |
| Hearing loss | May be present (Meniere's, labyrinthitis) | Usually absent |
| Tinnitus | May be present | Usually absent |
| Neurological symptoms | Absent | Often present (diplopia, dysarthria, dysphagia, ataxia) |
| Severity | Can be severe, but patient can compensate | Often less severe but more concerning |
Red Flags, Never Miss These
⚠️ Red Flag
The following features suggest central pathology and require urgent investigation (CT or MRI head):
- New headache at onset of vertigo (especially thunderclap or severe)
- Diplopia (double vision)
- Dysarthria (slurred speech)
- Dysphagia (difficulty swallowing)
- Facial numbness or weakness
- Limb weakness or sensory loss
- Ataxia out of proportion to vertigo
- Vertical nystagmus on examination
- No fatigability on Dix-Hallpike (cannot suppress)
- New deafness with no peripheral ear disease
- Risk factors: hypertension, atrial fibrillation, diabetes, age over 65
Peripheral Causes in Detail
BPPV (Benign Paroxysmal Positional Vertigo)
- Brief episodes lasting less than 60 seconds
- Triggered by head movement: rolling over in bed, looking up, bending forward
- No hearing loss or tinnitus
- Often worse in the morning, may resolve spontaneously over weeks
- Dix-Hallpike manoeuvre is the diagnostic test (positive if it reproduces vertigo with torsional nystagmus)
💎 Clinical Pearl
BPPV is the most common cause of vertigo in primary care. Knowing the Epley manoeuvre repositioning technique will impress examiners, even if you are not expected to perform it.
Vestibular Neuritis
- Single prolonged episode of severe vertigo lasting days to weeks
- Gradual improvement as the brain compensates
- No hearing loss (distinguishes it from labyrinthitis)
- Often follows a viral illness
- HINTS examination (Head Impulse, Nystagmus, Test of Skew) helps distinguish from posterior stroke
Meniere's Disease
- Classic triad: episodic vertigo + unilateral sensorineural hearing loss + tinnitus
- Episodes last 20 minutes to several hours
- Aural fullness (feeling of pressure in the ear) is a fourth feature
- Often progressive hearing loss over time
- Can be severely disabling
Labyrinthitis
- Same as vestibular neuritis but WITH hearing loss
- Usually follows a viral upper respiratory tract infection
- Severity often peaks in the first 24 hours then gradually improves
Social History
Always ask about:
- Falls: "Have you fallen because of this? Did you injure yourself?"
- Driving: "Are you currently driving? This is important because vertigo can be dangerous at the wheel."
- Work: "What do you do for work? Does this affect your ability to do your job?"
- Functional impact: "Are you able to manage around the house?"
Drug and Medication History
Several drugs can cause vertigo or dizziness:
- Aminoglycosides (gentamicin): ototoxic
- Loop diuretics (furosemide): ototoxic at high doses
- Antihypertensives: postural hypotension
- Antiepileptics (phenytoin, carbamazepine): cerebellar side effects
- Metronidazole, quinine, aspirin (high doses): tinnitus and hearing loss
Frequently Asked Questions
"How do you distinguish BPPV from a central cause of vertigo in the history?"
BPPV produces brief episodes of vertigo, lasting under 60 seconds, that are triggered by specific head movements: rolling over in bed, looking upwards, or tilting the head. There is no hearing loss, no tinnitus, and no neurological symptoms. Episodes are positional and fatigable. Central vertigo, particularly from a posterior fossa lesion or cerebellar stroke, produces vertigo that is not clearly positional, does not fatigue, and is often accompanied by neurological symptoms: diplopia, dysarthria, dysphagia, facial numbness, limb weakness, or truncal ataxia. The presence of any neurological symptom alongside vertigo must be treated as central in origin until proven otherwise.
"What is the classic triad of Meniere's disease?"
The classic triad of Meniere's disease is: episodic vertigo (lasting 20 minutes to several hours), unilateral sensorineural hearing loss (initially fluctuating, later progressive), and unilateral tinnitus. A fourth feature is aural fullness, a sensation of pressure or fullness in the affected ear, which often precedes or accompanies attacks. Attacks are unpredictable and can be severely debilitating. The underlying mechanism involves endolymphatic hydrops (increased pressure in the endolymph of the inner ear). In an OSCE history, ask specifically about the combination of hearing loss, tinnitus, and aural fullness alongside vertigo, as this combination is near-diagnostic and distinguishes Meniere's from vestibular neuritis, which has no cochlear component.
"What red flags in a dizziness history suggest you need urgent investigation?"
Red flags that suggest central pathology requiring urgent CT or MRI include: new or severe headache at the onset of vertigo (especially if sudden onset, suggesting subarachnoid haemorrhage or posterior fossa bleed); diplopia; dysarthria; dysphagia; facial numbness or weakness; new limb weakness or sensory loss; and marked ataxia disproportionate to the vertigo. On examination, vertical nystagmus or nystagmus that does not fatigue and changes direction with gaze direction suggests central pathology. Cardiovascular risk factors (hypertension, atrial fibrillation, diabetes, smoking, prior stroke) in an older patient with new vertigo should be treated as posterior circulation stroke until proven otherwise.
"How does postural hypotension present differently from true vertigo?"
Postural hypotension causes pre-syncope rather than true vertigo. The patient describes greyness of vision, feeling faint, or lightheadedness on standing, typically within 1-3 minutes of moving from lying to sitting or sitting to standing. They do not describe the world spinning. The mechanism is an inadequate blood pressure response to postural change, defined as a drop of 20 mmHg systolic or 10 mmHg diastolic within 3 minutes of standing. Common causes include dehydration, antihypertensive medications (particularly alpha-blockers and diuretics), autonomic neuropathy (diabetes, Parkinson's disease), prolonged bed rest, and adrenal insufficiency. Ask about timing (on standing), medications, and associated symptoms of fluid depletion.