title: Effect of castor oil emulsion eyedrops on tear film composition and stability.
abstract: OBJECTIVE
  An emulsion eyedrop containing castor oil has been shown to modify the tear film lipid layer and increase tear film stability. The primary objectives of this investigation were to measure the prevalence of castor oil in the tear fluid over time and quantify the effects on the lipid layer. A secondary objective was to quantify the initial effects on ocular symptomatology.
  
  
  METHODS
  The investigation was an open label pilot study on 5 normal and 10 dry eye subjects. A single eyedrop (Castor oil emulsion, Allergan) was instilled in each eye; the tear film appearance and composition were monitored for 4h via in vivo visualisation using the Tearscope and post in vivo tear samples analysis by HPLC.
  
  
  RESULTS
  Combined results for both normal and dry eye subjects showed that castor oil was detected up to 4h after a single eyedrop instillation and associated with an increase in the level of tear film lipid. The relative amount of various lipid families was also changed. An increase in tear lipid layer thickness was significant up to one hour post-instillation for the symptomatic sub-population. The changes in tear film characteristics were associated with significantly lower symptoms up to four hours post-instillation for the symptomatic sub-population.
  
  
  CONCLUSIONS
  This pilot investigation showed that castor oil eyedrops achieved a residence time of at least four hours post-instillation, producing a more stable tear film and an associated significant decrease in ocular symptoms over the entire follow-up period for the symptomatic subjects.
authors: OTG Research & Consultancy, London, UK. cmaissa@otg.co.uk
authors: Cécile
authors: C
authors: Maïssa
authors: Michel
authors: M
authors: Guillon
authors: Peter
authors: P
authors: Simmons
authors: Joseph
authors: J
authors: Vehige
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002368:Castor Oil / Q000008:administration & dosage*; D015352:Dry Eye Syndromes / Q000175:diagnosis* / Q000188:drug therapy*; D004655:Emulsions / Q000008:administration & dosage; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009883:Ophthalmic Solutions / Q000008:administration & dosage*; D010865:Pilot Projects; D013666:Tears / Q000737:chemistry*; D016896:Treatment Outcome
chemical_list: D004655:Emulsions; D009883:Ophthalmic Solutions; D002368:Castor Oil