Regular use of the drug ketamine can cause memory problems, say English researchers who conducted memory and psychological tests on 120 users and non-users.
Those who frequently used the drug -- dubbed Special K -- performed significantly worse when asked to recall names, conversations and patterns. Performance on the tests was even worse when the University College London researchers conducted a follow-up a year later, BBC News reported.
The study appears in the journal Addiction.
Ketamine, which is popular among club goers, acts as a stimulant and induces hallucinations. Previous studies have suggested the drug could cause bladder and kidney damage, BBC News reported.
Lead researcher Dr. Celia Morgan said "many young people who use this drug may be largely unaware of its damaging properties and its potential for addiction. We need to ensure that users are informed of the potentially negative consequences of heavy ketamine use."