Whitening effects last for up to 6 months to a year depending on Patient’s oral hygiene , intake of coloured foods , frequency of drinking tea/coffee/smoking etc. If maintained well , whitening can help you with a brighter smile for a year or so. You might have slight sensitivity post whitening which will go away in about 2 weeks after whitening.
Next Steps
Consult a dentist in your area for Professional whitening
Health Tips
Do not follow any quack advice through Internet