The Effect of Dosage of Caffeine on Intraocular Pressure

Not Applicable

• Conditions: Intraocular Pressure; Caffeine Dosage
• Interventions: Other: regular dose coffee; Other: decaffeinated coffee; Other: high dose coffee

• Registration Number: NCT01793311
• Lead Sponsor: Chiang Mai University

Brief Summary

The goal of the study is to determine the effect of different doses of caffeine on intraocular pressure. We hypothesized that higher dosage of caffeine would increase intraocular pressure more than lower doses.

Eligible subjects will be randomized into three groups:

1. group 1: intake of decaffeinated coffee

2. group 2: intake of coffee with lower caffeine dose

3. group 3: intake of coffee with higher caffeine dose

Intraocular pressure will be measured at 0, 30, 60 and 90 minutes after coffee intake.

Detailed Description

decaffeinated coffee contains 0.5-2 mg of caffeine regular dose coffee contains 91.8 mg of caffeine high dose coffee contains 144 mg of caffeine

all three groups' intraocular pressure will be measured with the Goldmann applanation tonometer at 4 timepoints:

1. 0 minutes (baseline)

2. 30 minutes after intake

3. 60 minutes after intake

4. 90 minutes after intake

Study Timeline

• Status Verified: 2013-02
• Study Start: 2013-02
• Study First Submitted: 2013-02-13
• Study First Submitted QC: 2013-02-14
• Last Update Submitted: 2013-02-14
• Study First Posted: 2013-02-15
• Last Update Posted: 2013-02-15
• Primary Completion: 2013-03
• Study Completion: 2013-03

Recruitment & Eligibility

• Status: UNKNOWN
• Sex: All
• Target Recruitment: 60

Inclusion Criteria

• healthy subjects
• normal central corneal thickness
• normal baseline intraocular pressure

Exclusion Criteria

• any ocular disease
• baseline intraocular pressure over 21 mmHg
• central corneal thickness less than 520 microns or more than 540 microns

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: PARALLEL

Arm && Interventions

Group	Intervention	Description
Group2: regular dose coffee	regular dose coffee	contains 91.8 mg of caffeine
Group1: Decaffeinated coffee	decaffeinated coffee	contains 0.5-2 mg of caffeine
Group3: high dose coffee	high dose coffee	contains 144 mg of caffeine

Primary Outcome Measures

Name	Time	Method
change from baseline in intraocular pressure (mmHg)after caffeine intake	0, 30 minutes, 60 minutes, 90 minutes post-caffeine intake	intraocular pressure measured at 4 timepoints: 1. 0 minutes (baseline); 2. 30 minutes after intake; 3. 60 minutes after intake; 4. 90 minutes after intake

Trial Locations

Locations (1)

Chiang Mai University Hospital; 🇹🇭 Muang, Chiang Mai, Thailand