Adverse events after chemodenervation with onabotulinum neurotoxin A in children with hypertonia and sialorrhea

Targeted injections with onabotulinum toxin A (Botox) have been used for close to 35 years to decrease spasticity (increased muscle tone) in children and adolescents. It is only within the last 5 years, however, that the Food and Drug Administration (FDA) has approved the use of Botox to manage spasticity in children aged 2 to 17 years. The FDA approved specific dose ranges and maximum doses based on weight and age.

Prior to the FDA approval of the use of Botox in children, highly variable and often much higher doses of Botox were injected into children to decrease spasticity. We wondered whether there was evidence that using higher doses of Botox causes more problems for children who are injected.

We reviewed 1733 episodes of injections in 648 patients who were seen in one pediatric hospital over the course of 3 years. We examined the medical records from the time of the injection through the 2 months following the injection. We compared the results in children who had FDA approved doses of Botox to the results in children who were injected with doses of Botox greater than that approved by the FDA.