A DRUG abuse expert has cast doubt on the effectiveness of a new Chinese detoxification treatment which claims faster results and a 100 per cent success rate. The treatment, known as One Plus One, is being used for the first time in a new drug rehabilitation centre in Shenzhen where staff claim 20 heroin addicts have kicked the habit in less than eight days. The centre, which has only the most basic of facilities in what appear to be highly unsanitary conditions, charges patients about $4,000 to be detoxified using the new treatment. When the Post visited the centre yesterday, vomit-stained bed-clothes and cigarette butts littered the dirty floors along with open pots of urine and faeces, while patients and staff lit up despite ''no smoking'' signs. But the centre's director, Zhang Jun, claims the new treatment is speedy, painless, very safe and totally reliable. He added: ''The treatment works very quickly in just five to eight days and we expect it to be used in other parts of China and other countries soon.'' The centre, which is supported by the Shenzhen Government and can cater for more than 80 patients, is billed as ''excellent'' with a ''good environment, confidential service and cheap rates''. The treatment, a secret formula which uses traditional Chinese medicine, is given by injection and puts the addict to sleep for five to six hours after which Mr Zhang claims patients feel much better and no longer crave heroin. He added: ''The treatment is much quicker and more effective than conventional detoxification programmes and so far no patients have come back to the centre.'' But a spokesman for the Society for the Rehabilitation of Drug Abusers (SARDA) in Hong Kong said the fact that no patients had returned did not necessarily mean they no longer had a drug problem. SARDA's deputy superintendent of social services Frankie Sun Kap-cheong added: ''I know nothing about this new treatment and so I cannot really comment on it specifically. ''But detoxification is only part of the rehabilitation process and in order to claim any sort of success rate there must be some follow-up on the patients to find out if they have remained free of drugs.'' At SARDA, drugs addicts are detoxified free of charge using methadone as a heroin substitute, with the dosage reduced gradually until the patient is drug free - usually within 21 days. But more than half of addicts detoxified through SARDA relapse and begin using heroin again. Mr Sun said: ''The most difficult part of the rehabilitation process is not detoxification but actually keeping the patient off drugs in the longer term.'' Mr Sun said that with so few addicts detoxified at the centre to date it was difficult to claim success. for the treatment.