Impact of medications on salivary flow rate in patients with xerostomia: a retrospective study by the Xeromeds Consortium

Objectives This study evaluates the impact of systemic medications and polypharmacy on unstimulated (UWS) and chewing-stimulated whole saliva (SWS) flow rates in patients with xerostomia. Material and methods This cross-sectional multicenter study is based on data of patients referred to five oral medicine outpatient practices in Europe and USA from January 2000 and April 2014. Relevant demographic, social, medical history and current medications were collected. Results The study included 1144 patients, 972 (85%) females, with a mean (SD) age of 59 (14.1) years. In unmatched patients, the UWS flow rate was lower in patients taking a medication (vs. not taking a medication) from the following drug categories: opioid analgesics, anticonvulsants, antidepressants, antihypertensives, benzodiazepines, corticosteroids, diuretics, disease-modifying antirheumatic drugs (DMARDs) and hormones. There was a greater negative effect on SWS flow rate in patients taking (vs. not taking) anticonvulsants, antidepressants, benzodiazepines, corticosteroids, and DMARDs. In matched patients, both UWS (0.22 vs. 0.19 ml/min; p = 0.03) and SWS (0.97 vs. 0.85 ml/min; p = .017) flow rates were higher in patients on non-opioid analgesics (vs. not taking). The UWS flow rate was lower in patients taking antidepressants (vs. not taking) (0.16 vs. 0.22 ml/min p = .002) and higher (and within normal range) in patients taking sex hormones (vs. not taking) (0.25 vs. 0.16 ml/min; p = .005). On the other hand, SWS was lower in patients taking corticosteroid (vs. not taking) (0.76 vs. 1.07 ml/min; p = .002), and in patients taking DMARDs (vs. not taking) (0.71 vs. 0.98 ml/min; p = .021). Finally, differences in medians of both UWS and SWS were statistically significant in patients taking 1 or more than 1 opioid analgesic (vs. not taking, p ≤ .0001 and p = .031, respectively), 1 or more than 1 anticonvulsants (vs. not taking, p = .008 and p = .007), 1 or more than 1 antidepressants (vs. not taking, p < .0001 for both), 1 or more than 1 DMARDs (vs. not taking, p = .042, and p = .003). Conclusions A greater negative impact on UWS and SWS flow rates was seen in patients taking more than one medication from the same drug class. Intake of antidepressants, corticosteroids and DMARDs is associated with lower whole saliva flow rates. Clinical relevance Salivary flow rate can be modified by some specific medications, mostly by polypharmacy.