De Moraes CG, et al. – Analysts test the hypothesis the intraocular pressure (IOP) peaks amid a stress test [the water drinking test (WDT)] can estimate the risk of future visual field progression in treated primary open–angle glaucoma (POAG) patients. It was concluded that the IOP peaks detected with the WDT were predictive of future visual field progression in a treated POAG population. This stress test could be a helpful tool for risk evaluation in daily practice.