A person who smokes can go for teeth whitening services. A dentist will examine your teeth strength & then give the appropriate consultation for teeth whitening. Actually teeth whitening procedure uses products that are sensitive to your teeth. A dentist checks the teeth strength & prescribe the suitable whitening treatment for you.
Whitening at the dentist is expensive and isn't always covered by insurance (cosmetic), but they do a better job than the OTC products. If you do get your teeth whitened, be prepared for them to be quite sensitive for a while. Usually the dentist will apply a fluoride treatment to help with the sensitivity and recommend that you use some kind of fluoride rinse.
The procedure involves a strong hydrogen peroxide solution and bright light. Teeth cleaning before whitening is recommended I think.
Extrinsic stain can be removed by prophylaxis procedure. After removal of extrinsic stain, then evaluate if you really need vital bleaching of natural tooth.