Safety of botulinum toxin type A in children younger than 2 years.

BACKGROUND: Botulinum toxin type A (BoNT-A) has been used in many indications and is licensed for the treatment of spasticity in children older than 2 years. However, there are few reports of BoNT-A treatment in patients younger than 2 years of age.

AIMS: To review retrospectively the safety data from all infants treated with botulinum toxin type A (BoNT-A) before 2 years of age in a paediatric neurology unit.

METHODS: There were 74 infants: 28 received the first dose before 1 year of age, and 46 between the ages of 1 and 2 years.

RESULTS: In the first year of life, the most frequent indication was obstetric brachial palsy (OBP) (71.4% of cases) and in the second year, cerebral palsy (CP) (73.9%). Both Botox and Dysport, the two commercially-available BoNT-A products in Spain, were used. The average starting dose by session was 6.55 U/kg body weight Botox in infants in their first year of life, and 8.4 U/kg body weight Botox and 21.1 U/kg body weight Dysport in the second year of life. Only 3.6% of cases treated in the first year and 6.5% of those treated in the second experienced adverse events (AEs), which consisted of mild weakness or tiredness lasting 1-4 days.

CONCLUSIONS: BoNT-A has a good safety profile in infants younger than 2 years old. AEs are similar to those found in older children.