Pore strips are perfectly safe to use as long as you follow their instructions. When used correctly, they can help remove blackheads, make your pores appear smaller and improve the overall appearance of your skin [source: WebMD]. However, if you overdo it, you could end up looking like you just had a chemical peel. Pore strips aren't meant to be used every day. In fact, you shouldn't use them more than once a week -- using them more frequently could irritate your skin.
The skin on certain areas of your face is more sensitive than others. For example, your cheeks tend to be more sensitive than your nose, so don't be surprised if using a pore strip on them leaves you with red, sensitive cheeks. You should also be careful if you're using a topical acne medication -- they can dry the skin and make it more sensitive to pores strips [source: Fried]. While it may seem counterintuitive, you also shouldn't use pore strips on areas of your face that are broken out. The skin around a pimple can be incredibly sensitive, and using a pore strip can irritate it further [source: Roppatte].
For more information on pore strips and their benefits, see the links on the following page.