The effects of chronic clomipramine treatment on the incidence of caries in the rat and their prevention by fluoride and pilocarpine were investigated. One hundred and twenty male Wistar rats were divided into six groups, five experimental groups, one control group and treated with 50 mg/kg/day of clomipramine, 10 ppm fluoride in drinking water, and 5 mg/kg/day of pilocarpine. All animals were infected with Streptococcus sobrinus 6715 and fed a cariogenic diet ad libitum for 42 days. Water and food consumption, weight gain, salivary flow rate, amylase activity, protein and fluoride concentration in saliva, and caries scores were determined in all animals. Whereas clomipramine significantly increased the fluoride and protein concentration in saliva, pilocarpine only decreased fluoride concentration. Animals treated with clomipramine developed 40% more sulcal caries than nontreated animals. Administration of fluoride (10 ppm) in drinking water and chronic oral administration of pilocarpine prevented the increased risk of developing caries associated with chronic treatment with clomipramine.