Using theTEMA (test system for development of medications for alcoholism) it can be shown, that naltrexone administration reduces the willingness to perform work for alcohol infusion in a laboratory experiment.
Name: Naltrexone
Name: Placebo
Description: Difference of cumulative number of work sets for alcohol in the "constant attention task" between first measurement (without medication) and second measurement (with medication)
Measure: Difference CAT Trials alcohol Time: one yearDescription: Difference of cumulative number of work sets for sodium chloride solution in the "constant attention task" between first measurement (without medication) and second measurement (with medication)
Measure: Difference CAT Trials sodium chloride solution Time: one yearDescription: Difference of the "break point" in the "progressive work" schedule for the work for alcohol between first measurement (without medication) and second measurement (with medication). The "break point" is the number of the last alcohol request before subjects stop to work for more alcohol.
Measure: break Point alcohol Time: one yearDescription: Maximal achieved blood alcohol concentration (BAC) in alcohol self-administration between first measurement (without medication) and second measurement (with medication)
Measure: max. BAC Time: one yearDescription: Drinking habits measured with Timeline Follow-back Interview over 45 days before study start (measured at screening) and over the entire study duration (between screening and the last day of medicinal product intake, ascertained at visit 5): drinking days, amount of alcohol per drinking day and number of days with alcohol consumption over 60 g (men) or 48 g (women)
Measure: Drinking habits Time: one yearDescription: CDT - level: (carbohydrate-deficient transferrin), measured at visit 1 and visit 5
Measure: CDT - level Time: one yearDescription: Alcohol craving in daily routine (OCD - scale) measured at visit 1 and visit 4
Measure: alcohol craving Time: one yearDescription: Difference in subjective alcohol effects between first measurement (without medication) and second measurement (with medication), measured with visual analogue scales ("Quizzer") before, during and after the alcohol infusion
Measure: subjective alcohol effects Time: one yearDescription: Capacity for motor impulse control during infusion of physiologic saline solution or alcohol as NIMPs (single-blinded), measured with the counting stroop task (in Verum and placebo group) at visit 3 and 4
Measure: motor impulse control Time: one yearDescription: Regional cerebral perfusion in ml/100 g tissue per Minute during infusion of sodium chloride solution or alcohol as NIMPs (single-blinded), measured with arterial spin labeling (ASL) under verum or placebo condition at visit 3 and 4
Measure: cerebral blood flow (CBF) Time: one yearDescription: Cerebral resting state activity during infusion of sodium chloride solution or alcohol as NIMPs (single-blinded), measured with BOLD fMRI (in Verum and placebo group) at visit 3 and 4
Measure: Cerebral resting state activity Time: one yearDescription: Medical survey concerning occurring adverse events at visit 1 to 5
Measure: adverse events Time: one yearDescription: ALAT (alanine aminotransferase) in µmol/ s*l before inclusion (screening visit), at visit 4 and after finishing all study relating interventions (visit 5)
Measure: ALAT Time: one yearDescription: ASAT (aspartate aminotransferase) in µmol/ s*l before inclusion (screening visit), at visit 4 and after finishing all study relating interventions (visit 5)
Measure: ASAT Time: one yearDescription: Gamma-GT in µmol/ s*l before inclusion (screening visit) and after finishing all study relating interventions (visit 5)
Measure: Gamma-GT Time: one yearDescription: standard blood cell count before inclusion (screening visit), at visit 4 and after finishing all study relating interventions (visit 5)
Measure: standard blood cell count Time: one yearDescription: creatinine in µmol/l before inclusion (screening visit)
Measure: creatinine Time: one yearDescription: lipase in µmol/ s*l before inclusion (screening visit) and after finishing all study relating interventions (visit 5)
Measure: lipase Time: one yearDescription: CRP (C-reactive protein) in mg / l before inclusion (screening visit) and after finishing all study relating interventions (visit 5)
Measure: CRP Time: one yearAllocation: Randomized
Parallel Assignment
There is one SNP
Secondary objectives: - administration of naltrexone in comparison to placebo leads to a reduction of alcohol craving and real-life drinking - administration of naltrexone in comparison to placebo leads to reduction of the CDT-Level - administration of naltrexone in comparison to placebo leads to a change in perception of subjective alcohol effects - the effectiveness of naltrexone can be predicted by the A118G polymorphism of the OPRM1 - administration of naltrexone changes the baseline and alcohol-induced ability of motor inhibition - administration of naltrexone changes the baseline and alcohol-induced regional cerebral perfusion - administration of naltrexone changes the baseline and alcohol-induced cerebral resting state activity - changes of alcohol effects to the brain activity induced by naltrexone in comparison to placebo correlate with effects of naltrexone on the willingness to work for alcohol self-administration --- A118G ---