A survey conducted by Chinese University of Hong Kong has shown, for the first time, that ketamine abusers with shorter histories of using the drug have a better chance of full recovery from damaged bladders after quitting the drug. 

"The earlier they quit the drugs, the higher potential the bladder will fully recover," Mak Siu-king, leading professor on the research at the Division of Urology at the Faculty of Medicine of Chinese University, said on Thursday. 

The bladder capacity of drug abusers who quit for more than one year is 387ml, about 40 percent more than those who have quit only recently, according to the survey. 

The dosage and amount taken over a certain period also has a significant bearing on bladder capacity, said Mak. 

For people who take three or more doses weekly, bladder capacity will be reduced to around 200ml, half of the capacity for an ordinary person. 

The research reveals that taking ketamine, a highly addictive drug, will result in bladder dysfunction, with symptoms such as urinary urgency and frequency, pelvic pain and urinary incontinence. 

The report also notes that, potentially, it takes about a year of abstinence to normalize bladder function. 

One drug abuser with a drug history extending more than 10 years said he needs to use the toilet every 15 minutes. It severely affects his work. His transportation options are limited since he lives one hour's travel from his office. 

"Most of the patients who come to hospitals seeking help are in their last stage of bladder problems," said professor Yip Kam-hung, at the Division of Urology at the university. 

"To draw a conclusion from our research, we suggest ketamine abusers quit the drug as soon as possible. 

"For ketamine users who have bladder problems, quitting the drug is the best antidote - more than any other medicines," said Yip. 

The survey, with the help of social workers, interviewed 66 young people, with an average age of 18, between July and September. 

The findings have been published in the Journal of Urology, an international refereed medical journal.