Improvement of Contact Lens Discomfort (CLD) via 'Eye Washing' Confirmed: Presented at the 68th Annual Meeting of the Japanese Contact Lens Society

Kobayashi Pharmaceutical Co., Ltd. (Headquarters: Osaka, President: Kazukazu Toyoda) and Professor Hiroshi Fujishima of the Department of Ophthalmology, Tsurumi University School of Dental Medicine (Headquarters: Yokohama, Kanagawa, President: Nobuyoshi Takada), have jointly demonstrated that 'eye washing' using commercially available eye wash solutions is an effective and safe self-care method for contact lens-related discomfort (CLD*¹). These results were presented orally at the 68th Annual Meeting of the Japanese Contact Lens Society held from May 29 to 31, 2026.

Key Research Findings ■ Improvement of CLD through Eye Washing Habits It was demonstrated that one month of eye washing habits significantly improves discomfort such as 'grittiness' experienced by contact lens wearers, based on both subjective feedback and objective 'tear film stability.' Along with the physical cleaning effect, the study suggests that active ingredients in the eye wash solution may contribute to tear film stabilization. ■ Safety Confirmed: No Adverse Effects after One Month of Continuous Use The study confirmed no adverse effects on tear mucin levels, bulbar conjunctival hyperemia, or protein adhesion to contact lenses, proving it to be a safe self-care practice.

<Research Background> Nearly half of contact lens wearers are estimated to experience CLD, which is gaining attention as a global issue. While eye drops are common for addressing this discomfort, 59% of those who use eye wash solutions are contact lens wearers, suggesting high expectations for 'eye washing.' Despite this, sufficient knowledge regarding the utility of eye washing had not been obtained. Therefore, a joint study with Professor Hiroshi Fujishima of Tsurumi University was initiated to explore the potential of eye washing as a self-care aid for improving CLD.

<Research Results> 1. Significant Improvement in CLD Twenty subjects wearing soft contact lenses (SCL) who met the discomfort criteria performed eye washing twice a day for one month. Results showed that subjective symptom scores via the J-CLDEQ-8 questionnaire significantly improved in both the saline and commercial eye wash groups (p<0.01), indicating that eye washing is useful for reducing CLD.

2. Safety Confirmed Evaluations of tear mucin levels (MUC5AC), bulbar conjunctival hyperemia, and protein adhesion on SCL surfaces showed no significant differences between the start and the end of the four-week period in either group. This indicates that eye washing is safe for soft contact lens wearers.

<Conclusion> This study confirmed that eye washing is safe for eyes wearing soft contact lenses and may be an effective self-care option for CLD. We will continue to propose eye washing habits to those suffering from CLD to contribute to more comfortable contact lens wear.