What are the differential diagnoses for a patient presenting with dizziness, considering factors such as age, sex, medical history, and current medications?

Differential Diagnoses for Dizziness

The differential diagnosis for dizziness is best organized by timing and triggers rather than the patient's subjective description of symptoms, as this approach more accurately distinguishes benign peripheral causes from dangerous central pathology. 1, 2

Classification by Timing and Triggers

Triggered Episodic Vestibular Syndrome (Brief, Positional)

Episodes lasting seconds to less than 1 minute, triggered by specific head or body position changes 1, 2:

• Benign Paroxysmal Positional Vertigo (BPPV) - Most common cause of peripheral vertigo (42% of cases in general practice), characterized by brief positional vertigo without hearing loss 1, 3
• Postural hypotension - Triggered by standing or position changes 1
• Perilymphatic fistula - Abnormal connection between middle and inner ear, may be triggered by pressure changes 1, 3
• Superior canal dehiscence syndrome - Abnormal opening in bone covering superior semicircular canal 1, 3
• Central paroxysmal positional vertigo - Rare central mimic of BPPV 1

Acute Vestibular Syndrome (Continuous, Days to Weeks)

Acute persistent continuous dizziness lasting days to weeks with nausea, vomiting, and intolerance to head motion 1, 2:

• Vestibular neuritis - Accounts for approximately 41% of peripheral vertigo cases 1, 3
• Labyrinthitis - Inflammation of inner ear with associated hearing loss 1, 3
• Posterior circulation stroke - Critical diagnosis; approximately 25% of acute vestibular syndrome cases have cerebrovascular disease, rising to 75% in high vascular risk cohorts 1, 3
• Demyelinating diseases - Including multiple sclerosis 1
• Posttraumatic vertigo - Following head trauma 1, 3

Spontaneous Episodic Vestibular Syndrome (Minutes to Hours)

Episodic dizziness not triggered by position, lasting minutes to hours 1, 2:

• Vestibular migraine - Extremely common and often under-recognized, accounting for 14% of all vertigo cases with lifetime prevalence of 3.2% 1, 2, 3
• Ménière's disease - Classic triad of episodic vertigo lasting hours, fluctuating sensorineural hearing loss, tinnitus, and aural fullness; accounts for 10% of cases in general practice 1, 3
• Posterior circulation transient ischemic attack - Episodes typically last less than 30 minutes; may precede stroke by weeks or months 1, 3
• Medication side effects - Including antihypertensives, sedatives, anticonvulsants, and psychotropic drugs 1, 2
• Anxiety or panic disorder - Common cause of spontaneous episodic symptoms 1, 2

Chronic Vestibular Syndrome (Weeks to Months)

Dizziness lasting weeks to months or longer 1, 2:

• Anxiety or panic disorder - Leading psychiatric cause 1, 2
• Medication side effects - Most common and reversible cause; review antihypertensives, sedatives, anticonvulsants, psychotropic drugs 1, 2
• Posttraumatic vertigo - Can persist chronically with vertigo, disequilibrium, tinnitus, and headache 1, 2
• Posterior fossa mass lesions - Including vestibular schwannomas and other tumors 1, 2
• Cervicogenic vertigo - Variable presentation 1

Additional Differential Considerations

Otologic Disorders

• Otosyphilis - Can mimic Ménière's disease with fluctuating hearing loss 1
• Acute labyrinthitis - Presents with fluctuating hearing loss, tinnitus, and aural fullness 1
• Ototoxic medications - Particularly aminoglycosides like gentamicin; can cause irreversible vestibular toxicity 3

Neurologic Disorders

• Vertebrobasilar insufficiency - Isolated attacks lasting less than 30 minutes without hearing loss 1, 3
• Central nervous system lesions - Various structural abnormalities 1

Medical Conditions

• Toxic, infectious, and metabolic conditions - Broad category requiring systemic evaluation 1
• Orthostatic hypotension - Particularly in elderly patients with age-related physiological changes 1, 2

Critical Distinguishing Features

Key Historical Elements to Elicit

• Duration: Seconds (<1 minute) suggests BPPV; minutes to hours suggests vestibular migraine or Ménière's; days to weeks suggests vestibular neuritis or stroke 1, 2
• Triggers: Positional changes (BPPV), spontaneous (vestibular migraine, Ménière's, stroke) 1, 2
• Associated symptoms: Hearing loss, tinnitus, aural fullness (Ménière's); headache, photophobia, phonophobia (vestibular migraine); focal neurologic deficits (stroke) 1, 2, 4
• Fluctuating hearing loss: Key distinguishing feature of Ménière's versus stable/absent hearing loss in vestibular migraine 1, 2, 3

Red Flags Requiring Urgent Neuroimaging

• Focal neurological deficits - Note that 75-80% of posterior circulation stroke patients have no focal deficits 2, 4
• Sudden unilateral hearing loss 2, 4
• Inability to stand or walk 2, 4
• New severe headache accompanying dizziness 2, 4
• Downbeating or other central nystagmus patterns 2, 4
• Failure to respond to appropriate vestibular treatments 2, 4

Common Diagnostic Pitfalls to Avoid

• Relying on patient's description of "spinning" versus "lightheadedness" instead of focusing on timing and triggers 2, 4
• Assuming normal neurologic exam excludes stroke - 75-80% of posterior circulation strokes have no focal neurologic deficits 2, 4
• Overlooking vestibular migraine - Extremely common but under-recognized, particularly in young patients 1, 4, 3
• Failing to distinguish fluctuating hearing loss (Ménière's) from stable/absent hearing loss (vestibular migraine) 1, 4, 3
• Ordering imaging for straightforward BPPV - Delays treatment unnecessarily 4, 3
• Overlooking medication side effects - One of the most common and reversible causes 1, 2
• Missing concurrent vestibular disorders - Patients can have multiple conditions simultaneously (e.g., BPPV with Ménière's disease) 3