Abstract: This paper reports the DHE substitution clinical trial in 38 heroin addicts. TheCINA(Clinical Institute Narcortic Assessment)scale was used to assess physical dependence potential.The CINA scale contains 10 opioid withdrawal signs(nausea ,vomiting ,gooseflesh,sweating,restless-ness , tremor , larcrimation , nasal congestion ,yawning ,changes in heart rate and systolic blood pres-sure)and 3 opiate withdrawal symptoms(abdominal pain , muscle pain and feeling hot or cold). For each subject admitted to the Drug Detoxification and Treatment Center his(her ) status oneach of the 13 items of CINA were immediately rated.Then ,naloxone 0.4 mg was injected iv toprecipitate withdrawal symptoms and at 5 ,10 ,15 min after the naloxone injection,the CINA scoreof each patient was rated again. The differences among the scores of pre-and post-naloxone injectionis a measurement of the degree of withdrawal symptoms.Then,a single dose of DHE wasadministered sublingually to each patient , all withdrawal symptoms disappeared. These results show that DHE can compete with naloxone for opioid receptors.A good Dose-response relationship was found between the 100%suppressive withdrawal sign doses of DHE and thedegree of withdrawal sign in heroin addicts.The physical dependence potential of DHE given to heroinaddicts sublingually was probably more than that of methadone given to heroin addicts orally by making reference to the report of Dr.Peachy⁽³⁾.