Effects of green tea on primary glaucoma

Effects of Green Tea Consumption on Retinal Nerve Fiber Layer ( RNFL) and Intraocular Pressure ( IOP) in Patients With Primary Glaucoma

Not applicable Interventional Universiti Sains Malaysia · NCT06235827

This study is testing whether drinking two cups of green tea every day can help lower eye pressure and protect vision in people with primary glaucoma.

Quick facts

PhaseNot applicable
Study typeInterventional
Enrollment100 (estimated)
Ages18 Years to 80 Years
SexAll
SponsorUniversiti Sains Malaysia Academic / other
Locations1 site (Kubang Kerian, Kelantan)
Trial IDNCT06235827 on ClinicalTrials.gov

What this trial studies

This randomized control trial aims to investigate the impact of green tea consumption on patients diagnosed with primary glaucoma. Participants will be divided into two groups: one group will consume two cups of green tea daily for six months, while the control group will not consume green tea. The study will measure changes in intraocular pressure (IOP) and retinal nerve fiber layer thickness (RNFL) at 1, 3, and 6 months. The goal is to determine if green tea, known for its antioxidant properties, can provide neuroprotective benefits for glaucoma patients.

Who should consider this trial

Good fit: Ideal candidates are patients with a confirmed diagnosis of primary glaucoma who have been on medical therapy for at least six months and have never consumed green tea regularly.

Not a fit: Patients with significant ocular media opacities, a history of optic neuropathy, or those allergic to green tea may not benefit from this study.

Why it matters

Potential benefit: If successful, this study could offer a dietary intervention that helps manage intraocular pressure and slows the progression of glaucoma.

How similar studies have performed: While the specific effects of green tea on glaucoma are not widely studied, other research has shown that antioxidants can have protective effects in various ocular conditions.

Eligibility criteria

Show full inclusion / exclusion criteria
Inclusion Criteria:

* Patient with confirmed diagnosis of primary glaucoma (POAG/PACG/NTG) that achieve target IOP with medical therapy at least for 6 months.
* Never consume green tea as daily drinks.

Exclusion Criteria:

* Dense cataract with Lens Opacity Classification Sytem (LOCS II) of more than grade 2
* Any other ocular media opacity that may interfere with OCT imaging ( eg: cornea scar/vitreous haemorrhage)
* Any history of optic neuropathy
* History of glaucoma or retinal surgery
* Macular degeneration and retinal disorder
* Patient with caffein sensitive that causes unpleasant reaction (eg: palpitation, insomnia, nausea, constipation)
* Allergic to green tea

Where this trial is running

Kubang Kerian, Kelantan

Study contacts

How to participate

  1. Review the eligibility criteria above with your treating physician.
  2. Visit the official trial page on ClinicalTrials.gov for the most current contact information and recruitment status.
  3. Contact the listed study coordinator or principal investigator to request pre-screening. Pre-screening is free and never obligates you to enroll.
Conditions Primary Glaucoma
Last reviewed 2026-06-13 by the Find a Trial editorial team. Information on this page is for educational purposes and is not medical advice. Always consult qualified healthcare professionals about clinical trial participation.