What causes sudden dizziness that lasts for a few seconds and then resolves?

Generally, sudden dizziness lasting for a few seconds that quickly resolves may be caused by orthostatic hypotension, excessive mental tension, benign paroxysmal positional vertigo (BPPV), Ménière’s disease, or transient ischemic attack (TIA). It is recommended to seek timely medical evaluation to determine the underlying cause and receive appropriate symptomatic treatment under a doctor's guidance. Specific analyses are as follows:

1. Orthostatic hypotension: Suddenly standing up after prolonged sitting or lying down causes blood to pool momentarily in the lower body, leading to temporary cerebral hypoperfusion and dizziness. To prevent this, rise slowly—sit or lie still briefly before gradually standing. Maintain adequate daily fluid intake to avoid dehydration.

2. Excessive mental tension: Sudden emotional stress such as anxiety or fear can cause vasoconstriction and nervous system dysregulation, resulting in brief episodes of dizziness. Maintain emotional stability through deep breathing, distraction techniques, and avoiding intense emotional fluctuations.

3. Benign paroxysmal positional vertigo (BPPV): Dislodged otoliths stimulate the semicircular canals, triggering brief dizziness with changes in head position. Patients should follow medical advice for canalith repositioning procedures. Medications such as betahistine, flunarizine hydrochloride capsules, or difenidol tablets may also be used to relieve symptoms.

4. Ménière’s disease: Abnormal metabolism of inner ear lymph leads to endolymphatic hydrops, causing vertigo and tinnitus. Under medical supervision, patients may use medications like betahistine mesylate tablets, hydrochlorothiazide tablets, or dexamethasone tablets to reduce inner ear fluid accumulation and control symptoms.

5. Transient ischemic attack (TIA): Temporary blockage or spasm of cerebral blood vessels results in brief cerebral ischemia and hypoxia, manifesting as dizziness. As directed by a physician, antiplatelet drugs such as enteric-coated aspirin, clopidogrel, or atorvastatin calcium tablets may be prescribed. In some cases, carotid endarterectomy may be considered to prevent thrombus formation.

Maintain a regular lifestyle, avoid staying up late, and engage moderately in gentle exercises such as walking or tai chi to improve physical health. Eat a balanced diet, reduce intake of high-fat and high-salt foods, and maintain healthy levels of blood pressure, blood glucose, and blood lipids to help prevent dizziness episodes.