Effect of caffeine on the intraocular pressure in patients with primary open angle glaucoma

Figures & data

Figure 1 The bars represent the intraocular pressure of patients given caffeine eye drops as described for Table 1 (the 1-day study).

Notes: The times indicated sequentially represent measurements A to D. The extended lines on the bar represent standard deviations.

Table 1 Effect of caffeine eye drops on intraocular pressure: 1-day treatment study

	A	B	C	D
Mean IOP	23.6	23.2	22.2	22.6
Standard deviation	2.8	1.93	1.99	2.31
t with A reference		0.37	1.3	0.87
Variance (p)/A*		0.71	0.21	0.4

Notes: (A) represents the basal IOPs (mmHg). (B) represents the values soon after the first treatment. To look for a possible cumulative effect, eye drop instillation was repeated after 4 hours (C) and 6 hours (D) and IOP determined 30 minutes after each administration. The total number of eyes was ten, using the right as well the left eyes of five subjects. Contralateral difference was 1.4 ± 0.69 mmHg.

* Variance (p) of the IOPs under B, C, and D with referece to the IOP under A, based on the corresponding t values indicated above.

Abbreviation: IOP, intraocular pressure.

Figure 2 The bars represent the intraocular pressure on patients given caffeine eye drops as described under Table 2, (the 1 week study).

Notes: The times indicated sequentially represent measurements A to D. The extended lines on the bar represent standard deviations.

Table 2 Effect of caffeine eye drops on intraocular pressure: 1-week study

Groups	A	B	C	D
Mean IOP	22.6	23.0	22.4	23.0
Standard deviation	2.32	2.16	2.27	1.94
t with A reference		0.39	0.19	0.48
Variance (p)/A		0.69	0.85	0.68

Note: After 6 days of 3 times daily application, the procedure described in Table 1 was repeated with identical times of drop instillation and IOP measurements. The total number of eyes remained at ten, using the right as well the left eyes of five subjects. Contralateral difference was 1.3 ± 0.99 mmHg.