Benign Paroxysmal Positional Vertigo (BPPV): This condition is a common cause of dizziness, especially in adolescents, due to its association with head or neck trauma, viral infections, or even simple actions like rolling over in bed. The brief but intense episodes of vertigo triggered by specific head movements make it a likely diagnosis.

Vasovagal Syncope: A common cause of dizziness and fainting spells in adolescents, often triggered by stress, pain, or prolonged standing. The body's vasovagal response can lead to a sudden drop in blood pressure, resulting in dizziness or syncope.
Anxiety or Panic Disorder: Anxiety and panic disorders can manifest with symptoms of dizziness, among others like palpitations, sweating, and fear of losing control. The psychological component can sometimes be overlooked in the differential diagnosis of dizziness.
Orthostatic Hypotension: This condition involves a significant drop in blood pressure upon standing, leading to dizziness or lightheadedness. It can be due to dehydration, medication side effects, or autonomic dysfunction.

Cardiac Abnormalities (e.g., Long QT Syndrome, Wolff-Parkinson-White Syndrome): Although less common, cardiac issues can cause dizziness due to arrhythmias or structural heart defects. Missing these diagnoses can be fatal, making them critical to rule out.
Central Nervous System (CNS) Disorders (e.g., Multiple Sclerosis, CNS Tumors): CNS disorders can present with a wide range of symptoms, including dizziness. Early diagnosis is crucial for effective management and prognosis.
Infections (e.g., Meningitis, Encephalitis): Infections affecting the CNS can cause dizziness among other severe symptoms. Prompt recognition and treatment are vital to prevent serious complications or death.

Migraine-Associated Vertigo: Some individuals experience vertigo as part of their migraine syndrome. While not the most common cause of dizziness, it's an important consideration, especially in adolescents with a history of migraines.
Chiari Malformation: A structural defect in the cerebellum that can cause dizziness, among other symptoms like headaches and neck pain. It's a rare condition but one that requires surgical intervention in some cases.
Autoimmune Disorders (e.g., Lupus, Rheumatoid Arthritis): Certain autoimmune disorders can have neurological manifestations, including dizziness. These conditions are rare but important to consider in the differential diagnosis due to their potential for significant morbidity if left untreated.