The present invention relates to a glucocorticoid (GC) for use in the amelioration, treatment or prophylaxis of neurological/psychiatric adverse events caused by a CD3 binding domain. Kits comprising a GC, a CD3 binding domain and instructions for use which indicate that the GC is to be employed for the treatment amelioration and/or prophylaxis of neurological adverse events caused by said CD3 binding domain, are also disclosed.