How long should you wait to smoke after teeth whitening?

A temporary effect of teeth whitening is the dehydration of tooth enamel.  There is an increased risk during this period for dyes and stains to affect the tooth shade/color.  After the teeth re-hydrate, your teeth will be more resistant to picking up stains, although it still happens.  To be on the safe side I would wait at least 48 hours before smoking (also, stay away from coffee, tea and berries) after the whitening appointment.  However, you will see better and longer results from whitening if you stay away from smoking altogether.