Use of saliva in home monitoring of carbamazepine levels.

Total carbamazepine (CBZ) levels in serum of 61 epileptic children were compared with saliva levels. Both resting and stimulated saliva was analyzed. The salivary levels were 38.6% of serum CBZ levels. A highly significant correlation was noted (r = 0.89, p < 0.001). Stimulation had no effect on saliva CBZ levels (r = 0.97). Salivary and serum CBZ levels were not affected by storing the samples for 7 days at room temperature. The data indicate that salivary CBZ may provide a reliable alternative monitoring method to Tegretol therapy, especially in children, in whom blood sampling is difficult. Furthermore, the samples may be collected at home and delivered to the laboratory by mail.