I had to turn in my bifocal lenses for repair. I have monofocal lenses to use in the meantime, i have to use them to drive. However, I can’t read with them. I have a variety of loupes and magnifying glasses. Would it hurt my eyes to use them with my backup glasses? Or, should i take off my glasses when i use the magnifying glasses?
Since pretty much my vision is useless without my glasses I’ve used additional lenses - magnifying, microscope, binocular, telescope - along with my glasses all my life. no sign of problems so far. Well, OK, it can be a little awkward juggling all the vision accessories but using them in that manner won’t hurt you.
Be sure not to let the lenses touch each other. I’ve done that with binoculars and one of them is going to scratch.
There should be a problem for your eyes if you use another lens to see things clearly. The warning against magnifier lenses is that they can mask more serious problems (the real reason someone needs them may be something like macular degeneration or some other issue), but if you go to an optometrist regularly, they can find that.
For an obvious example, I have the compact OED and wear glasses. I use the magnifier to read it (or did before I could get to it online); there’s no other way to do it, glasses or not.