title: Downbeat nystagmus due to ranitidine in a pediatric patient.
abstract: BACKGROUND
  Ranitidine has not been considered as a potential cause of ocular movement conditions. However, it is known that the vestibular nucleus complex, that has a key role in gaze control and vestibule-ocular reflexes, receives hypothalamic histaminergic innervations. Some studies reported the effect of ranitidine blocking the excitatory responses of vestibular nuclei neurons to histamine.
  
  
  METHODS
  We report the first case of a downbeat nystagmus secondary to ranitidine in an infant. A 3-month-old female developed a downbeat gaze after starting treatment with ranitidine for a pediatric gastroesophageal reflux disease. Microbiological test were negative and neuroblastoma evaluation was normal.
  
  
  CONCLUSIONS
  As ranitidine is widely prescribed in the pediatric population, clinicians should be aware of its potential to cause ocular movements disorders.
authors.affiliation: Department of Pediatrics, Hospital General Universitario Gregorio Marañón, Madrid, Spain. Electronic address: laura_bl@hotmail.com.
authors.forename: Laura
authors.initials: L
authors.lastname: Butragueño Laiseca
authors.affiliation: Department of Pediatrics, Hospital General Universitario Gregorio Marañón, Madrid, Spain.
authors.forename: Blanca
authors.initials: B
authors.lastname: Toledo Del Castillo
authors.affiliation: Department of Pediatrics, Hospital General Universitario Gregorio Marañón, Madrid, Spain.
authors.forename: Cristina
authors.initials: C
authors.lastname: Rodríguez Jimenez
authors.affiliation: Pharmacy Service, Gregorio Marañón General and Teaching Hospital, Gregorio Marañón Health Research Institute, Research Network on Maternal and Child Health and Development II (Red SAMID II), Spanish Health Institute Carlos III, Madrid, Spain.
authors.forename: Silvia
authors.initials: S
authors.lastname: Manrique-Rodríguez
authors.affiliation: Department of Pediatrics, Hospital General Universitario Gregorio Marañón, Madrid, Spain.
authors.forename: Jimena
authors.initials: J
authors.lastname: Pérez Moreno
mesh_terms: D000897:Anti-Ulcer Agents / Q000009:adverse effects*; D005260:Female; D005764:Gastroesophageal Reflux / Q000188:drug therapy; D006801:Humans; D007223:Infant; D009759:Nystagmus, Pathologic / Q000139:chemically induced*; D011899:Ranitidine / Q000009:adverse effects*
chemical_list: D000897:Anti-Ulcer Agents; D011899:Ranitidine
keywords: Infant; Nystagmus; Ocular movement disorder; Ranitidine