Acta Scientific Ophthalmology (ISSN: 2582-3191)

Research Article Volume 4 Issue 1

Long-term Effects of Eyewash Solution Use on the Conjunctival Bacterial Flora

Takafumi Saeki1*, Miho Tanaka1, Manabu Nozaki1, Hiroko Yano1, Hiroyuki Yazu2 and Hiroshi Fujishima2

1Research and Development Department, Healthcare Division, Kobayashi Pharmaceutical Co., Ltd., Osaka, Japan
2Department of Ophthalmology, Tsurumi University School of Dental Medicine, Kanagawa, Japan

*Corresponding Author: Takafumi Saeki, Research and Development Department, Healthcare Division, Kobayashi Pharmaceutical Co., Ltd., Osaka, Japan.

Received: December 15, 2020; Published: December 29, 2020



Purpose: Commercial eyewash solutions are widely used in Japan for the removal of foreign bodies from the ocular surface and relief from unpleasant symptoms, and many individuals use them daily. However, the effects of habitual eye washing on the conjunctival bacterial flora have not been investigated yet. In this study, the bacterial flora in healthy eyes was evaluated after one month of continuous use of a commercial eyewash solution.

Methods: In total, 29 participants with healthy eyes were recruited. Eyebon® W, a commercial eyewash solution available in Japan, was used as the test eyewash. The eyes were randomly designated as treatment (group 1) and no treatment (group 2). The eyes in group 1 were washed twice daily with Eyebon® W for one month. The eyes in group 2 were not treated with any eyewashes or eye drops. Samples were collected from the inferior palpebral conjunctiva. Ultimately, a sufficient amount of cDNA for analysis was obtained from 11 individuals (22 eyes). The viable bacterial count was determined and the bacterial flora was analyzed using next-generation sequencing of 16S rRNA amplicons.

Results: In both groups, the bacterial flora was mainly composed of 6–7 genera. There were no statistically significant differences in the average rates for each genus in the conjunctival bacterial flora, regardless of the eyewash condition (P > 0.05).

Conclusion: Our findings suggest that washing eyes twice a day using eyewash is unlikely to have a significant impact on the conjunctival bacterial flora.

Conclusion: Eyebon®; Eyewash; Ocular Surface; Microbial Flora; Safety; Long Time-use



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Citation: Takafumi Saeki., et al. “Long-term Effects of Eyewash Solution Use on the Conjunctival Bacterial Flora”.Acta Scientific Ophthalmology 4.1 (2021): 27-42.


Acceptance rate35%
Acceptance to publication20-30 days
ISI- IF1.042
JCR- IF0.24

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