I think you should consult with your doctor. Because it may be harmful to you to use this drop. After all its eye problem. And you should eat proper diet fruits which are helpful to your eye.
You should stop these drops right away. I don't know what eye brightening drops are. I would strongly recommend an exam with an ophthalmologist to determine why your eyes are red. Until that appointment, you could try artificial tears like Refresh, Systane, or Blink. Any of these products can be used 4 times a day. If you need a tear drop more than that, it should be preservative free.