Can whitestrips unstain my teeth?

Yes but limited: If your staining is superficial the best way to get rid of the is a cleaning at your dentist, if it is intrinsic or deep the the whitening strips can help, but dont rely on them to make your teeth gleeming white. See your dentist for more options.

Yes but: Whitestrips can whiten teeth but not as much as professional products can. So don't get your expectations up too high.

Sort of. Many limitations. Best Rx is 1) Have teeth professionally cleaned to remove superficial stain. 2) Have dentist provide you with best in-office or take-home whitening program for your individual needs. 3) See Dentist every 6 months for examination and professional cleaning. If your teeth, gums, supporting bone are not healthy, all the whitening in the world won't help.