Parotid Gland Edema After Chlorhexidine Mouthrinse: Case Report and Literature Review

Introduction: Parotid gland swelling, caused by many pathological conditions, has also been reported to be a possible side effect of the use of chlorhexidine mouthwash. This adverse reaction to chlorhexidine mouthwash is, however, extremely rare and very few cases of parotid gland swelling due to chlorhexidine mouthwash have been reported in the literature. Case Description: This report describes the clinical management of unilateral parotid swelling caused by chlorhexidine mouthwash. Methods: A patient presented with left parotid gland swelling after using chlorhexidine mouthwash for three days following sinus augmentation on the contralateral side of the maxilla. Diagnosis of parotid gland swelling due to rinsing with chlorhexidine was formulated after anamnesis, clinical examination, radiographs and ultrasound of the gland excluded other pathological conditions. The patient was subsequently advised to stop rinsing. However, on the evening of the same day, swelling increased and the patient presented to an emergency department where a single intravenous dose of methylprednisolone was administered. Results: After seven days, parotid swelling decreased significantly and after three weeks had completely disappeared. Conclusion: Although unilateral or bilateral parotid gland swelling related to the use of chlorhexidine mouthwash is an uncommon adverse event, it must be suspected after other organic or infective conditions have been excluded. The precise pathogenic mechanism has not yet been determined and further studies should be carried out to better understand the pathophysiology of this uncommon phenomenon.