NEW YORK (Reuters Health) – The problem of drooling in children with neurological disorders can be relieved in about half of cases by injections of botulinum toxin into the submandibular salivary glands, with the benefit lasting about 5 months, a Dutch team reports.

Dr. Arthur R. T. Scheffer of Radboud University Medical Center, Nijmegen, and colleagues note in the September issue of the Archives of Otolaryngology–Head & Neck Surgery that intraglandular botulinum toxin was first suggested a decade ago, and has been in use in the authors’ multidisciplinary drooling clinic since 1999.

“It is often assumed that drooling in neurologically challenged children is more or less intractable. There are, however, several treatments,” Dr. Sheffer told Reuters Health via email. “Our study shows botulinum toxin (Botox) is quite effective, and contrary to many other therapies, has very few side effects. Its effects are reversible, and the treatment can be repeated if necessary.”

For their study, the researchers prospectively documented outcomes in 131 children with cerebral palsy or other nonprogrogressive neurological disorder who had moderate to severe drooling.

Under general anesthesia, the children were given a single dose of botulinum toxin type A into the submandibular glands, fractionated to at least three sites. The dose ranged from 15 to 25 U depending upon the child’s weight.

Sixty-one of the children had at least a 50% reduction in drooling. In these responders, drooling remained below 50% of baseline for a median duration of 22 weeks.

“As we have studied so many children, we are able to provide more evidence for the magnitude of botulinum toxin’s effect, and how long this effect is likely to last,” Dr. Scheffer commented. “This is especially important in the decision-making for parents or caretakers, as these physically and mentally handicapped children are usually incapable to make medical decisions themselves.”

Asked about the need for general anesthesia, he responded: “It is possible to administer the injections while children are awake. However, we feel that this is usually more traumatic to these children than general anesthesia. We have experienced no problems with our approach.

While the injections were generally well tolerated, there were some side effects. Some children had thickening of saliva, while in others saliva viscosity was reduced. A few had transient difficulty swallowing, and changes in feeding behavior were reported in some.

Noting the relatively low (albeit useful) response rate of 46.6%, the authors conclude that improving patient selection should be a focus in future studies.

Arch Otolaryngol Head Neck Surg 2010; 136:873-877.