Treatment of acanthamoeba keratitis with chlorhexidine

Ophthalmology. 1999 Apr;106(4):798-802. doi: 10.1016/S0161-6420(99)90169-0.


Objective: To evaluate the efficacy of chlorhexidine solution in the treatment of patients with Acanthamoeba keratitis.

Design: Prospective nonrandomized study.

Participants: Five patients infected with culture-proven Acanthamoeba keratitis.

Intervention: Chlorhexidine solution was used hourly on six eyes and gradually reduced to four times a day after 1 month. Follow-up ranged from 1 to 10 months (mean, 4 months).

Main outcome measures: Severity of symptoms and signs, time for healing, and final visual acuity.

Results: Clinical results in four patients showed improved visual acuity, with a rapid recovery within 1 week. No adverse drug reaction was encountered, but one patient with a perforated ulcer developed glaucoma. Eighty-three percent of 6 eyes were medically cured with chlorhexidine and recovered visual acuity 6/18 or better. Four of five patients improved within 3 weeks, with resolution of infiltration and healing of epithelial defects. By 2 to 3 weeks, visual acuity 6/18 or better had improved in four (66.7%) of six eyes and recovered 6/6 in two eyes (33.3%). Bacterial coinfection occurred in one eye.

Conclusion: Chlorhexidine dramatically hastened clinical improvement in all eyes and is a successful medical therapy that has excellent results in patients who are diagnosed early.

Publication types

  • Case Reports
  • Clinical Trial

MeSH terms

  • Acanthamoeba / isolation & purification
  • Acanthamoeba Keratitis / drug therapy*
  • Adult
  • Aged
  • Animals
  • Anti-Infective Agents, Local / adverse effects
  • Anti-Infective Agents, Local / therapeutic use*
  • Chlorhexidine / adverse effects
  • Chlorhexidine / therapeutic use*
  • Cornea / parasitology
  • Female
  • Humans
  • Male
  • Middle Aged
  • Ophthalmic Solutions / adverse effects
  • Ophthalmic Solutions / therapeutic use
  • Prospective Studies
  • Safety
  • Treatment Outcome
  • Visual Acuity


  • Anti-Infective Agents, Local
  • Ophthalmic Solutions
  • Chlorhexidine