Are there any treatments or medications for both incontinence and glaucoma?

There aren't any medications specifically designed to treat both incontinence and glaucoma at the same time. 

That said, it's possible that prescription drops prescribed to treat glaucoma can affect the rest of the body. So, if your parent has both conditions, it may be worthwhile to make sure that the medications for her glaucoma don't make her incontinence worse, or vice versa.

Without knowing more about the kind of incontinence your parent has, I can't offer more specific information. Do make sure, though, that your parent's primary care doctor knows she's using glaucoma drops and ask if they're likely to affect her incontinence.  Her eye doctor should also know your parent has incontinence and what medications, if any, she takes for this condition.

The more information your parent's doctors have about her, the better care they can provide.