The number of children in England requiring treatment for ketamine use has nearly tripled in recent years, as doctors warn of the “harrowing” physical impact the drug is having on young users.
New data from the UK’s first specialist clinic for children with ketamine-related bladder damage reveals that some patients as young as 13 are suffering from a condition that causes them to “pee a jellyfish”—a term used by patients to describe the physical shedding of their bladder lining.
Analysis of the first 60 patients treated at the Alder Hey Children’s NHS Foundation Trust in Liverpool shows that patients are as young as 13. Clinicians found that two-thirds of the children treated were girls, and a significant majority—72%—had experienced childhood emotional trauma.
The ‘jellyfish’ effect and bladder damage
The phrase “peeing a jellyfish” refers to clumps of the bladder lining that detach due to the toxicity of the drug. As the bladder wall becomes severely inflamed and scarred, it loses its ability to hold urine, leading to what is known as ketamine-induced uropathy (KIU).
Symptoms reported by young patients include:
- Extreme pain during urination.
- Passing blood or visible tissue (the “jellyfish” effect).
- A frequent, urgent need to urinate, sometimes as often as every 10 to 15 minutes.
- Incontinence and sleep deprivation due to constant pain and bathroom visits.
Medical experts warn that while some damage can be managed if use is stopped immediately, severe cases can lead to irreversible fibrosis. This can necessitate major surgery, including the total removal of the bladder or lifelong dialysis.
Rising national figures
The clinical findings coincide with a sharp rise in national statistics. According to GOV.UK substance misuse reports for 2024/25, there were 1,465 children under the age of 17 in treatment for ketamine use in England. This is a significant increase from 512 children in 2021/22.
The specialist clinic at Alder Hey Children’s NHS Foundation Trust is currently the only dedicated facility in the UK for under-16s suffering from these specific urological complications.
Vulnerable demographics
Clinicians are urging parents and caregivers to be aware of the early warning signs of bladder damage, noting that children often hide their symptoms due to the stigma associated with drug use.
Practical advice for those concerned about a child’s health includes monitoring for sudden changes in bathroom habits or reports of pelvic pain. Health professionals stress that the most critical step is to stop the use of the drug immediately to prevent further, potentially permanent, damage to the urinary system.
Support and information for young people and families are available nationally through the Talk to FRANK service and local NHS drug and alcohol partnerships.