An increasing number of young patients with severe bladder overactivity syndrome potentially caused by recreational ketamine use has been treated in our department. Ketamine has become a popular and increasingly used recreational drug in New Zealand. Ketamine bladder syndrome has been reported internationally; however, local New Zealand data do not exist. It can lead to irreversible damage to the bladder, and internationally, surgical procedures like cystectomy and urinary diversion or augmentation cystoplasty have been reported as necessary treatments.