Short answer ... yes.
Long answer .. it depends on what you are going to do with them. They are toxic to us if we handle them and then put our hands in our mouths (although I doubt too many people are THAT silly). If you were to put the strip in the cage with the reptile .. yes, it would harm them. If they can contact it directly it would harm them, but if the strip is hanging in the same room (and not too close, or above the cage) I doubt it would be too bad. I would not let the reptile adventure beneath the strip either .. there could well be residue that falls, or even dead flies that don't stick .. that would be nasty if your critter tasted one of those.
I had a problem with fruit flies too .. so I got preying mantises .. put them in a screen cage on top of my gecko cage .. hehe .. bugfest. It didn't get rid of them totally, but it sure was fun watching the carnage.