Can caffeinated tea or coffee increase eye pressure in glaucoma patients?

Unlikely. Factors that affect intraocular pressure are varied and multifactorial and not completely understood. Effect of caffiene probably negligible.
Possibly. There was a recent study that showed caffein can temporarily increase your eye pressure. However, it was a small sample, so its hard to interprete the results. Some of the other things that can temporarily increase eye pressure: wearing neckties and lifting heavy weights. But i normally don't advise my glaucoma pts not to drink coffee or wear neckties or lift weights.
Very unlikely. Drinking extreme amounts of fluid of any kind can increase the volume of the vitreous jelly in side the eye and this can raise eye pressure but one would have to consume many gallons.

Related Questions

Regarding glaucoma will 3 cups of coffee in the morning raise eye pressure?

Minimally. There might be a brief, non-dangerous elevation as the fluid gets into the body, but your kidneys will quickly take care of that. Don't give up your morning coffee on this account. Read more...
Minimally if any. Caffeine in beverages like coffee has a very minimal effect on raising iop. A reportable albeit slight increase in iop has been shown and except rarely would have to be eliminated from someone with glaucoma. Read more...

I heard that target eye pressure for most glaucoma patients should be 14 - 15. Is that true?

Some variation. Normal eye pressure range is 10-21. Glaucoma is when eye pressure exceeds eye resistance to that pressure and varies with the individual case. 14-15 is generally a good target for most cases but some require a lower pressure and some can tolerate higher pressures. Your optimum can be decided with the help of your ophthalmologist. Read more...
Maybe. Average eye pressure is between about 12-21mmhg. The target eye pressure is different for each patient depending on the individual patients eye pressure and the level of optic nerve damage. This can be determined by your eye md after examination and testing. Target eye pressure may need to be adjusted over time depending on the stability of your exam and testing. Read more...