The prospective study of effect of ifenprodil on relapse prevention in patients with substance dependence

INTERVENTION: Prior administered group: patients administered control drug (vitamin C, product name: Cinal, 600mg/day) during 3 months after ifenprodil (product name: Cerocral, 60mg/day) during 3 months Latter administered group: patients administered ifenprodil during 3 months after control drug during 3 months CONDITION: Alcohol dependence PRIMARY OUTCOME: 1) Slip: alcohol use during the past month; 2) Level of alcohol drinking: frequency and amount of alcohol drinking; 3) Dropout: dropout of treatment; 4) Craving and relapse risk: assessment by self‐rating questionnaire including VAS and Alcohol Relapse Risk Scale (ARRS) INCLUSION CRITERIA: 1) Outpatients diagnosed as alcohol dependence 2) Stabilized patients who can complete the questionnaire 3) Patients in abstinence within 2 years 4) Patients who can respond in Japanese 5) Patients suspected mild cognitive deficiency from the results of a test of cognitive functions (or existing brain image data)