Botulinum Toxin to Reduce Saliva Flow: Selected Indications for Ultrasound‐Guided Toxin Application Into Salivary Glands

Abstract

Objectives/Hypothesis: The study investigates the effect of local injections of botulinum toxin type A (Botox) into the major salivary glands of the head in various states of hypersalivation. In particular, we studied pathological states with permanent as well as passing hypersalivation disorders and present new indications for local application of botulinum toxin to the salivary glands. Study Design: Retrospective clinical investigation. Methods: A total of 55 to 65 units of Botox were injected under sonographic control into the left and right parotid and submandibular glands of four patients with hypersalivation resulting from head and neck carcinoma, tracheostomy, and "idiopathic" hypersalivation disorder. At defined time intervals following injection, flow rate, total protein and immunoglobulin A content, and the enzymatic activities of amylase, acid phosphatase, and kallikrein were determined in the saliva. The patients were clinically examined to assess the severity of their symptoms, including sonographic control of the major salivary glands. Results: All four patients reported distinct improvement of their symptoms within 1 week after injection. Salivary flow rate had considerably dropped, whereas the concentrations of the salivary components were much increased. Sonography did not reveal any changes of the salivary gland parenchyma. Therapeutic side effects were absent. Conclusions: Treatment of hypersalivation by local injections of Botox into the salivary glands of the head is a reliable and efficient therapy without side effects for certain otolaryngological diseases, especially if injections are performed under sonographic control. Extension of this therapeutic concept to other indications is suggested.

Thickened saliva after effective management of drooling with botulinum toxin A

“…10 Previous studies have focused on the effect of BoNT-A on salivary proteins such as secretory immunoglobulin A (immune system) and amylase (digestion), but salivary mucins, which are responsible for the rheological properties of saliva, have not previously been studied. 11,12 In view of the anticholinergic properties of BoNT-A, it is likely that the watery component of saliva will be reduced and that the concentration of mucins will increase after BoNT-A injection. The present study was undertaken to investigate the viscoelasticity of saliva after BoNT-A injection and to evaluate the consequences of changed viscoelasticity.…”

“…11,12 However, previous studies focused on the effect of BoNT-A on salivary proteins such as secretory immunoglobulin A (immune system) and amylase (digestion): salivary mucins, which are responsible for the rheological properties of saliva, to our knowledge have not previously been studied. 11,12 In contrast to the secretion of the other salivary proteins, the secretion and the function of salivary mucins are dependent on water. 10 In case of dehydration, mucins might be secreted in plugs rather an a smooth film of mucus.…”

Symptomatic Treatment of Multiple Sclerosis

“…Pronounced hypersalivation may be attenuated using anticholinergic drugs [262] or by local injection of botulinum toxin A into the salivary glands as has been demonstrated in patients with ALS and Parkinson’s disease [268,269,270]. Botulinum toxin A applied to the superior esophageal sphincter may reduce dysphagia due to an elevated sphincter tone [271].…”

Immunohistochemical Evidence of nNOS and Changes after Intraglandular Application of Botulinum Toxin A in Cephalic Salivary Glands of Adult Rats

“…Our findings presented here, however, are in contrast to results of experiments with guinea pigs [8] where no difference in immunoreactivity could be found in the nasal mucosa between glands treated with either botulinum toxin or physiological saline. The influence of toxin treatment on the activity of nNOS in the cephalic salivary glands of the rat described by us could explain the sometimes longer duration of the toxin effect at the neuroglandular junction than at the motor endplate which has been found in clinical studies [5,6,14,15].…”

“…Since it is known that botulinum toxin A (Botox ® ) diminishes acetylcholinesterase activity [3,4], it was the aim of the present study to find out if the toxin also interferes with the metabolic actions of NO, especially at the neuroglandular synapsis. Extended knowledge about the mode of botulinum toxin action may be helpful in its clinical application for reducing salivary flow in hypersalivation states [5,6].…”