Recently diagnosed w/open angle glaucoma and being treated w/ 1 drop.. in general, how long is it before you know if glaucoma is under control?

Glaucoma : Glaucoma is generally defined as optic nerve damage (from high eye pressure or other causes), which can lead to changes and decreases in vision (the visual field of vision). Eye drops are the first line of therapy which try to lower pressure & maintain a steady daily eye pressure. Most drops usually take 1-2wks to do this. This is one of many factors involved in slowing down glaucoma progression.

Within two weeks: The intraocular pressure will change within 2 weeks. Additional drops may be needed. The ideal pressure will depend on your visual fields, and changes in your nerve.

When the outcome: Measured is not changing quickly. I.E. Visual fields stable, or oct rnfl measurement stable or, iop reaching expected target range, etc. After many months, you can have a good idea if things are stable.

Quickly: presumably you had elevated pressure in your eye. The drop given should lower the pressure within a week. Your ophthalmologist ( you are seeing an ophthalmologist for such a diagnosis?) will have you come back soon to see if the eye pressure responded to normal with your drop.