title: A significant drug-drug interaction detected through corneal examination: resolution of cornea verticillata while using amiodarone.
abstract: OBJECTIVE
  To describe a patient with resolution of cornea verticillata while still using amiodarone as a result of a drug interaction lowering serum levels of amiodarone.
  
  
  METHODS
  An 83-year-old retired physician with long-standing cornea verticillata was noted to have complete resolution of cornea verticillata on a routine follow-up eye examination. The patient reported complete compliance with using amiodarone daily, with no recent changes in dosage or formulation. Despite this, he reported a recent increase in the frequency of palpitations. He had recently started rifampin for treatment of tuberculosis.
  
  
  RESULTS
  Serum amiodarone and desethylamiodarone levels were obtained and found to be below therapeutic range. After rifampin was discontinued, serum amiodarone and desethylamiodarone levels increased to a therapeutic range and cornea verticillata returned after 4 months.
  
  
  CONCLUSIONS
  In patients currently using amiodarone, clearing of cornea verticillata should alert the ophthalmologists to the possibility of decreased serum amiodarone levels.
authors.affiliation: Scheie Eye Institute, Department of Ophthalmology, University of Pennsylvania School of Medicine, Philadelphia, PA 19104, USA.
authors.forename: Sonia
authors.initials: S
authors.lastname: Mehta
authors.forename: Vatinee Y
authors.initials: VY
authors.lastname: Bunya
authors.forename: Stephen E
authors.initials: SE
authors.lastname: Orlin
authors.forename: Michael E
authors.initials: ME
authors.lastname: Sulewski
authors.forename: Joshua L
authors.initials: JL
authors.lastname: Dunaief
mesh_terms: D000369:Aged, 80 and over; D000638:Amiodarone / Q000009:adverse effects* / Q000097:blood; D000889:Anti-Arrhythmia Agents / Q000009:adverse effects* / Q000097:blood; D000904:Antibiotics, Antitubercular / Q000009:adverse effects*; D003318:Corneal Opacity / Q000139:chemically induced*; D004347:Drug Interactions; D006801:Humans; D008297:Male; D012293:Rifampin / Q000009:adverse effects*; D014397:Tuberculosis, Pulmonary / Q000188:drug therapy
chemical_list: D000889:Anti-Arrhythmia Agents; D000904:Antibiotics, Antitubercular; D000638:Amiodarone; D012293:Rifampin