Randomized trial of botulinum toxin injections into the salivary glands to reduce drooling in children with neurological disorders

Abstract

The primary aim of this randomized, controlled trial was to assess the effectiveness of botulinum toxin A (BoNT-A) injections into the submandibular and parotid glands on drooling in children with cerebral palsy (CP) and other neurological disorders. Secondary aims were to ascertain the duration of any such effect and the timing of maximal response. Of the 48 participants (27 males, 21 females; mean age 11y 4mo [SD 3y 3mo], range 6-18y), 31 had a diagnosis of CP and 15 had a primary intellectual disability; 27 children were non-ambulant. Twenty-four children randomized to the treatment group received 25 units of BoNT-A into each parotid and submandibular gland. Those randomized to the control group received no treatment. The degree and impact of drooling was assessed by carers using the Drooling Impact Scale questionnaire at baseline and at monthly intervals up to 6 months postinjection/baseline, and again at 1 year. Maximal response was at 1 month at which time there was a highly significant difference in the mean scores between the groups. This difference remained statistically significant at 6 months. Four children failed to respond to the injections, four had mediocre results, and 16 had good results. While the use of BoNT-A can help to manage drooling in many children with neurological disorders, further research is needed to fully understand the range of responses.

Ultrasonography guided botulinum toxin a injection for excessive drooling in children

“…Previous studies reported success rates between 61.5% and 83% (2,7,(17)(18)(19). Our short-term success rate was 80%, and this result is in line with previous studies.…”

“…In addition to submandibular glands, parotid gland injections could have been considered as an alternative for unresponsive patients. In previous studies, the reason(s) for different responses to intraglandular BTX-A was not clarified (17)(18)(19).…”

“…Mild side effects, such as viscous saliva, chewing difficulties, dry mouth and transient weakness of mouth closure have been reported in the literature (2,6,(7)(8)(9)(10)(11)(12)(13)(14)(15)(16)(17)(18)(19). The majority of these side effects occur due to the muscle weakness that is related to the diffusion of the BTX outside the salivary gland (7).…”

Negative effects of submandibular botulinum neurotoxin A injections on oral motor function in children with drooling due to central nervous system disorders

“…6 The duration of this effect was approximately 2 to 6 months (median 24wks). [6][7][8] In most of these studies, botulinum neurotoxin A (BoNT-A) was used. …”

“…6 The duration of this effect was approximately 2 to 6 months (median 24wks). [6][7][8] In most of these studies, botulinum neurotoxin A (BoNT-A) was used. 9 Considering the increasing use of BoNT for drooling, studies to identify possible risk factors for adverse effects on oral motor functions before treatment are urgently needed.…”