What commonly causes horizontal nystagmus (abnormal eye movement), otitis media (middle ear infection), or symptoms related to alcohol intoxication?

From the Guidelines

Benign paroxysmal positional vertigo (BPPV) is the most common cause of horizontal nystagmus, and it can also be associated with symptoms similar to otitis media and alcohol intoxication. The vestibular system, located in the inner ear, controls balance and spatial orientation. When this system is disrupted, it can lead to abnormal eye movements (nystagmus) as the brain attempts to stabilize vision. BPPV is a disorder of the inner ear characterized by repeated episodes of positional vertigo, and it is most commonly thought to be due to canalithiasis, wherein fragmented otolith particles (otoconia) entering the posterior canal become displaced, cause inertial changes to the cupula in the posterior canal, and thereby result in abnormal nystagmus and vertigo when the head encounters motion in the plane of the affected semicircular canal 1.

Key Points

• BPPV can cause horizontal nystagmus, which is a rapid, involuntary oscillatory movement of the eyeball 1.
• Otitis media can directly affect the vestibular system by causing inflammation that extends from the middle ear to the inner ear structures, leading to symptoms similar to BPPV 1.
• Alcohol intoxication affects the vestibular system by altering the density of the fluid in the inner ear, which impairs the brain's ability to interpret balance signals correctly, resulting in symptoms similar to BPPV 1.
• Other causes of vestibular dysfunction include vestibular neuritis, Meniere's disease, and certain medications 1.
• Treatment depends on the underlying cause but may include vestibular rehabilitation exercises, medications for symptom relief, or addressing the primary condition such as antibiotics for bacterial otitis media 1.

Diagnosis and Treatment

• The supine roll test is the preferred maneuver to diagnose lateral canal BPPV, which is a type of BPPV that can cause horizontal nystagmus 1.
• Proper diagnosis is essential as these symptoms can sometimes indicate more serious neurological conditions, such as vestibular migraine, brainstem and cerebellar stroke or transient ischemic attacks, and intracranial tumors or disorders 1.
• Treatment of BPPV with canalith repositioning procedures (CRPs) can improve quality of life and reduce symptoms of vertigo and nystagmus 1.

From the FDA Drug Label

The FDA drug label does not answer the question.

From the Research

Horizontal Movement of the Eyes, Otitis Media, or Alcohol Intoxication

• The most common cause of horizontal nystagmus (abnormal eye movement) is related to otitis media, specifically serous labyrinthitis caused by acute otitis media (AOM) 2.
• Studies have shown that patients with otitis media have increased chances of having vestibular symptoms, including nystagmus, delayed acquisition of developmental milestones, and abnormalities in several vestibular function tests compared to controls 3.
• In adult patients with acute otitis media (AOM) or otitis media with effusion (OME) without dizziness, nystagmus was observed in 82% of patients, with the most common pattern being irritative-type direction-fixed nystagmus 4.
• Recurrent acute otitis media (rAOM) in children can lead to lasting balance and vestibular dysfunction, highlighting the importance of early monitoring and potential rehabilitation 5.
• Central ocular motor disorders, including gaze palsy and nystagmus, can be caused by various factors, including cerebellar dysfunction, brainstem lesions, and chronic alcohol abuse 6.
• Gaze-evoked nystagmus (GEN) in all directions can indicate cerebellar dysfunction and can have multiple causes, such as drugs, chronic alcohol abuse, neurodegenerative cerebellar disorders, or cerebellar ataxias 6.

Otitis Media and Vestibular Symptoms

• Otitis media has been associated with vestibular symptoms, including nystagmus, delayed acquisition of developmental milestones, and abnormalities in several vestibular function tests 3.
• The evidence suggests that patients with otitis media have increased chances of having vestibular symptoms compared to controls 3.
• However, the evidence supporting this association is based on low-quality evidence, and better-structured studies are warranted to better understand the clinical relevance of this association 3.

Alcohol Intoxication and Nystagmus

• Chronic alcohol abuse can cause cerebellar dysfunction, leading to gaze-evoked nystagmus (GEN) in all directions 6.
• Alcohol intoxication can also cause nystagmus, but the exact mechanisms are not fully understood 6.
• Treatment options exist for some disorders related to nystagmus, including miglustat for Niemann-Pick type C (NP-C) and aminopyridines for downbeat nystagmus (DBN) and upbeat nystagmus (UBN) 6.