Reduction of salivary flow with botulinum toxin: extended report on 33 patients with drooling, salivary fistulas, and sialadenitis

Abstract

Objectives/hypothesis: The aim of the study was the evaluation of the clinical data of 33 patients who had had drooling attributable to various diseases, salivary fistulas, and sialadenitis and had been treated with injection of botulinum toxin type A (Botox). A controlled follow-up study documenting efficiency, possible side effects, and duration of the effect of treatment was also performed.

Study design: Retrospective clinical evaluation.

Methods: Thirty-three patients with drooling attributable to head and neck carcinoma, neurodegenerative diseases, stroke, or idiopathic hypersalivation or with salivary fistula or chronic sialadenitis received injections of 20 to 65 U botulinum toxin type A into salivary glands under sonographic control. The entire salivary flow rate and the output per minute of the salivary analytes thiocyanate, total protein, alpha-amylase, acid phosphatase, kallikrein, and immunoglobulin A were measured at various times before and after injection. The patients were examined with regard to severity of their symptoms, including sonographic control investigation of their cephalic salivary glands.

Results: Twenty-six patients (79% of all patients) reported a distinct improvement of their symptoms after toxin injection. Seven patients noted a return of high salivation rates and requested a second injection after 4 to 7 months. Duration of toxin effect varied widely among individuals. In general, salivary flow rates and thiocyanate output dropped sharply within 1 week after injection and had increased again after a period of 12 to 16 weeks. Conversely, amylase outputs increased during this period, whereas the outputs of the other analytes remained roughly constant. Sonography did not reveal any major changes in salivary gland parenchyma, and side effects were not noted.

Conclusion: Reduction of salivary flow in patients with drooling, salivary fistulas, or chronic sialadenitis by local injection of botulinum toxin type A into the salivary glands proved to be a dependable therapy for these disorders, as shown in the present extended report on 33 patients. Side effects were not observed. The effect of toxin application lasted for approximately 3 months. Based on their results, the authors recommend botulinum toxin injection as the therapy of choice in patients with the problem of drooling.