1000 Section - Context of dose or drug change during neurological complications of botulinum toxin: a secondary analysis of a French pharmacovigilance study

The use of botulinum toxin in the fields of neurology and PRM is common. A previous pharmacovigilance study reports that neurological complications related to botulinum toxin are often serious, but with good prognosis. The aim of this study is to provide a more precise description of the clinical context of these complications, with reference to the context of dose or drug change.

Design:

A nationwide pharmacovigilance study of all neurologic adverse drug reactions (ADRs) related to use of botulinum toxins in France in the fields of neurology and PRM between 1994 and 2024.

Results:

In total, 204 people with systemic neurologic complications (ie, distant from the injection site) and 66 with local complications were included. Median (IQR) age was 54 (39;66) years, and 155 (57%) were women. The most frequent cases were systemic complications following injections for spasticity (154/270; 57%) and for detrusor overactivity (25/270; 9%). In 32% of cases, patients treated for spasticity already had a complication during a previous injection; and 31% of cases if the treatment was for detrusor overactivity. Sixty-seven percent of systemic complications after injection for spasticity were associated with a dose change (MD: 52%). In case of no dose change, systemic complications were associated with a drug change in 23% of injections for spasticity (MD: 32%), and in 22% of injections for detrusor overactivity (MD: 18%).

Conclusion:

In this pharmacovigilance study, systemic neurologic complications occurring after a botulinum toxin injection were mostly associated with a dose change.