What are the red flags for dizziness and vertigo?

Red Flags Requiring Emergency Assessment

The following features alongside dizziness/vertigo suggest a potentially life-threatening cause (stroke, cardiac event, or serious neurological condition):

Neurological red flags (posterior circulation stroke/TIA):

• Focal neurological deficits: limb weakness or numbness, facial droop
• Dysarthria, diplopia, dysphagia, dysphonia
• Gait ataxia or severe truncal ataxia (inability to sit unsupported or walk)
• Downbeat nystagmus, pure torsional nystagmus, or bidirectional gaze-evoked nystagmus (central nystagmus patterns)
• New severe headache ("thunderclap" or unlike previous headaches)
• Depressed consciousness or confusion

Cardiac red flags:

• Chest pain, shortness of breath, or palpitations
• Syncope or pre-syncope

Other red flags:

• Acute unilateral hearing loss with vertigo (anterior inferior cerebellar artery territory)
• Dizziness following head trauma
• New-onset vertigo with fever and severe headache (consider CNS infection)

Key Clinical Considerations

The HINTS Exam

In patients with acute vestibular syndrome (continuous vertigo >24 hours with nystagmus), the bedside HINTS exam is critical:

• Head Impulse test: Normal (no corrective saccade) = worrisome for central cause
• Nystagmus: Direction-changing or vertical = central
• Test of Skew: Positive (vertical ocular misalignment) = central

HINTS plus incorporates acute hearing loss assessment, improving diagnostic accuracy.

High-Risk Populations

In older adults, dizziness is frequently multifactorial, and there is increased likelihood of serious underlying causes such as stroke or cardiovascular disease; a comprehensive assessment including medication review, sensory evaluation, and careful neurological/cardiac examination is essential.

Episodic Vertigo Red Flags

Recent-onset, brief recurrent episodes of dizziness lasting only minutes should raise concern for vertebrobasilar TIA, even if dizziness is the only symptom.