The aim of the present study was to detect efflux transporter induction at salivary glands. Six healthy volunteers were involved. On the first day subjects received a single carbamazepine (CBZ) dose of 400 mg. Couples of salivary samples (first and second fraction, S1 and S2) were collected throughout time after dosing. The following 6 days subjects received 200 mg every twelve hours, and morning pre-dose samples were collected.