A study of the effectiveness and side effects of salivation-inducers in patients with Sjögren’s syndrome ～ Comparison between cevimeline hydrochloride and pilocarpine hydrochloride ～

Objectives: Cevimeline hydrochloride (CH) and pilocarpine hydrochloride (PH) are recognized as salivation-inducers with a high affinity for M3 muscarinic receptors. However, these drugs have a high frequency of side effects, including digestive symptoms and hyperhidrosis. We compared the effectiveness and side effects of these two drugs before and after a medication change.Materials and Methods: Seventy-six patients with Sjögren's syndrome were divided into the following four groups: 1) CH group, CH was administered for 12 months; 2) PH group, PH was administered for 12 months; 3) CH-PH group, CH was administered for 6 months followed by PH for 6 months; 4) PH-CH group, PH was administered for 6 months followed by CH for 6 months. We measured the salivary flow rate and recorded the subjective symptoms in each group.Results: In each group, stimulated whole saliva (SWS) and unstimulated whole saliva (UWS) significantly increased after 3 months and 6 months, respectively, and subjective symptoms improved after 3 months. The incremental changes in both SWS and UWS did not differ significantly between the groups. The CH and PH groups both had digestive symptoms (32.3% and 32.1%, respectively) and hyperhidrosis (29.0% and 39.3%, respectively). We found no significant difference in salivary flow rate or subjective symptoms after the medication change. However, the frequencies of side effects in the CH-PH and PH-CH groups decreased significantly for both digestive symptoms (9.7% and 10.7%, respectively) and hyperhidrosis (25.8% and 14.3%, respectively).Conclusions: After changing the salivation-inducing drug, there was no significant difference in salivary function or subjective symptoms, while the frequency of side effects markedly decreased. These results suggest that changing the salivation-inducing drug effectively reduces side effects.