patients with alcohol abuse and dependence may suffer from psychiatric disorder , and there is a high prevalence of alcohol and other drug use disorders among patients with schizophrenia and other psychotic disorders  shown to be as high as 50% in some studies.13 a high prevalence of alcohol abuse and substance use disorders has also been found in patients with first - episode psychosis.4,5 while alcohol - induced psychotic disorder is a well - recognized clinical disorder , relatively little is known about the mechanism of this condition . previous studies have reported decreased -aminobutyric acid ( gaba , inhibitory)6 and increased plasma glutamate and aspartate in patients who consume alcohol,7 while a placebo - controlled study reported superior efficacy of the inhibitory neurotransmitter glycine in reducing hallucinations in patients.7 certain genetic variants ( alleles ) , particularly the adh1b*2 , adh1b*3 , adn1c*1 , and aldh2 * 2 alleles , which code for alcohol - metabolizing enzymes such as alcohol dehydrogenase ( adh ) and aldehyde dehydrogenase ( aldh ) , have been associated with lower rates of alcohol dependence.8 the presence of these alleles may lead to an accumulation of acetaldehyde during the alcohol metabolism process , which can result in heightened subjective and objective effects.8 furthermore , the existence of an acute brain syndrome manifested by psychotic reaction to alcohol without regard to the amount of alcohol consumed has been well - described in the past.9,10 the acute , chaotic disruption of behavior resulting from ingestion of a small quantity of alcohol , known as  pathological intoxication  , has long been recognized as a psychiatric entity.11 pathological intoxication ( pi ) , also called alcohol idiosyncratic intoxication , was said to occur predominantly in persons with low tolerance to alcohol , but its existence as a definable syndrome is still controversial.12 the disease has been defined as an acute brain syndrome manifested by a marked behavioral or psychotic reaction after minimal alcohol intake in people with no preexisting mental disorder.12 the essential points of all the definitions of this disease were the following : 1 ) marked maladaptive behavioral change ( usually aggressive or assaultive behavior ) with minimal alcohol intake , 2 ) the behavior is atypical of the person when not drinking , and 3 ) cause not being any other physical or mental disorder according to dsm - iii - r ( diagnostic and statistical manual of mental disorders third edition revised).13 although pi had been listed in previous dsm editions , dsm - iv omitted it because of lack of supporting evidence to show that it was distinct from regular alcohol intoxication . furthermore , such a condition of pi would be mostly likely diagnosed as alcohol intoxication or alcohol - related disorder according to dsm - iv to dsm - v . there was also some evidence of pi in the people s republic of china , and only ten published case reports of pi have been identified upon a chinese language literature review from 1984 to 2012 . the data for this review were based on the chinese language literature identified from searches of the china national knowledge infrastructure ( www.cnki.net ; 19792012 ) , which is the largest online chinese language literature database . blood alcohol concentration was not measured in any patient , none of them showed unsteady gait and were inarticulate . besides , all had absolute aggressive behavior changes , and the duration of the episode was quite short and ceased after a few minutes to several hours . most of them were young , and four of them had accompanying schizophrenic symptoms such as visual hallucination or delusion . in the current study , we report a 24-year - old man , without a known psychiatric history of psychotic or affective disorder , who developed a unique , brief psychotic disorder following ingestion of small quantities of alcohol , which seems very different from pi . mr z. is a 24-year - old , previously healthy college student who developed psychotic features after drinking beer on the evening of june 15 , 2011 . ten minutes after having drunk two glasses ( ~200 ml ) of beer ( alcoholic strength of the beer was less than 4% ) , he was agitated and screaming , saying that his parents were in danger and that he should go to save them . he also masturbated in public without feeling shy although there were two female classmates around . following this , he was sent to the hospital immediately . at the time of admission , he demanded strongly that the door be closed and curtains be drawn over the windows . when he saw his father , he grabbed both of his father s hands tightly as if he feared losing his father . he closed his eyes but did not sleep the entire night , and he also called his father s name every 5 minutes to ensure that his father was around . he looked at the curtain all through the night from the bed , watching the shadow that the light of street lamp cast through the curtain , and listened to the noise of cars as if waiting for something to happen . nuclear magnetic resonance imaging ( mri ) scan of the brain and 24-hour ambulatory electroencephalogram examination revealed no remarkable changes . self - rating anxiety scale and self - rating depression scale were administered to him , and the scores of the two scales were 50 and 28 . there were no other mental records for him as he was unwilling to complete any more tests . at the time of admission , blood was routinely drawn to determine the blood alcohol level , perform routine blood examination , and assess hepatic and renal function and serum electrolyte level . blood alcohol level on admission was 30 mg / dl ( 6.52 mmol / l ) , and other blood examination results were normal . besides , the time span between ingestion of alcohol and blood alcohol level testing was very short there was no evidence of auditory or visual hallucination , delusions of reference , or other psychotic symptoms . he had not experienced stress or other traumatic experiences before . besides , there was a drinking history for the patient : he had consumed alcohol only one or two times in the past 3 months far from alcohol abuse and dependence . for this reason , it was considered that the current situation was an episode of brief psychotic symptoms , but not schizophrenia spectrum or other psychotic disorders . so , the doctor began therapy with seroquel ( quetiapine ) 25 mg qn initially . the doctor felt that his mental state returned to normal and that his symptoms resolved completely . he was discharged on the treatment of seroquel ( quetiapine ) 50 mg / night . when he went back school 1 week later , he did not take medication as before . he still studied well in school as before and showed no unusual behavior or symptoms . approximately 40 days later , he had drunk approximately 150 ml of beer with his father and his relatives . we started therapy with seroquel ( quetiapine ) 25 mg / night ( as before ) . furthermore , the patient did not experience any psychotic symptoms or behavior change in between these two episodes . approximately 30 days later , his symptoms recurred again because he had drunk three glass of beer , approximately 150 ml . his mental state returned to normal and his symptoms resolved completely 4 days after he took the medicine . he has since stopped taking the medicine and also does not drink alcohol any more . in the present report , we described the case of a young patient who presented with three episodes of behavioral change of acute onset suggestive of the brief psychotic episodes . interestingly , each of the hospital admissions was triggered by small quantities of alcohol consumption . the symptoms manifested mainly as thought blocking ; psychosensory disturbance ; public masturbation ; insecurity without elevated , expansive , irritable mood ; or other psychotic symptoms . the patient returned back to normal after therapy . both the mri scanning of the patient s brain and 24-hour ambulatory electroencephalogram were unremarkable . furthermore , the patient and his family had no history of psychotic or affective disorder , personality disorder , or a seizure disorder . there was a very light history of drinking for the patient , and there was no weird behavior before when he consumed alcohol . what surprised us most was that once he had drunk such a small amount alcohol , his behavioral reaction started to emerge . to our knowledge , there is no related literature reporting the occurrence of such type of symptoms after ingestion of a small quantity of alcohol . alcohol addiction or withdrawal could induce psychotic symptoms,14 but it seems that the patient in our case was far from such circumstances . the patient had no history of alcohol abuse and dependence , but had drunk beer only one or two times in the 3 months before the first episode . also , blood alcohol concentration at admission was low ( only 6.52 mmol / l ) , and the amount of beer ingested was small and the alcoholic strength of beer he consumed was less than 4% . several differences should be pointed out when comparing these disease characteristics to that of pi . in our case , the patient experienced a marked behavioral change , such as public masturbation , but no aggressive or assaultive behavior . in addition , the duration of the episode in our patient ( ~37 days ) was much longer than that in the cases with pi , which lasts for only several minutes or hours.1012 besides , most pi patients presented total amnesia for the period of the episode,12 while in our case the patient had partial amnesia . subsequently , when we used seroquel to treat the patient , he started to do better . also , episode of pi normally end with sound asleep.1012 in conclusion , there was insufficient evidence to demonstrate that the patient might suffer from pi or other alcohol - related neuropsychiatric disorders , although the episodes were induced by ingestion of a tiny amount of alcohol . although the patient showed atypical psychotic symptom without evident hallucination or delusion in these three episodes , the childish mannerisms and bizarre behavior still relates to or is characteristic of schizophrenia . besides , the age of onset is 24-year - old ( very young ) however , the one noteworthy point was that the patient would return to normal every time after therapy with seroquel ( quetiapine ) . as the evidence accumulates , we have more confidence to speculate that the patient might be exhibiting early symptoms of schizophrenia and that ingestion of small amount of beer might induce the episode accidentally . in other words , ingestion of small amount of alcohol might be one of the predisposing factors of the episode of atypical psychotic symptoms in our case . theoretically speaking , other issues , such as negative life events , might also induce psychosis . the patient presented with irritability , psychomotor agitation , and insomnia after drinking beer , which also fulfils the dsm - iv criteria for catatonia . catatonia is a clinical syndrome characterized by alterations in motor behavior , and changes in thought and mood and can occur in the context of several disorders , including neurodevelopmental , psychotic , bipolar , depressive disorders , and other medical conditions . catatonia has been documented as occurring in alcohol withdrawal in rodents , and rarely in humans , but not occurring in alcohol drinking.15,16 another possible diagnosis for this case was delirium . a patient with general delirious symptoms including thought process and sensory disturbances may fulfill the dsm - iv criteria for delirium . however , our patient exhibited no clouded consciousness , disorientation , or disturbed circadian rhythms , so this was not a possible diagnosis in this case . clinical studies have documented a significant degree of comorbidity between anxiety disorders and alcohol use disorders . previous studies , including both animal and human , have shown that acute exposure to low - to - moderate doses of ethanol are anxiolytic,17,18 and ingestion of small amount of ethanol resulted in development of anxiety symptoms in our patient . one possible reason for this could be that acute ethanol ingestion in our patient was associated with an acute decrease in gaba concentrations of the brain , and studies ( in humans and animals ) have shown that gaba deficits may induce stress and anxiety.19,20 taken together , this case demonstrates a special presentation of a marked behavioral change , which is suggestive of an episode of brief psychotic symptoms , after ingestion of small quantities of alcohol . and we can only assume , from the evidence and analysis , what disease the patient might be having . as a psychiatrist , it is essential to advise the patient not to drink any more , and , satisfactorily , he was also studying well at school during the follow - up period of 3 months .
psychotic symptoms can occur in some clinical conditions related to alcohol , such as intoxication , withdrawal , and other alcohol - induced neuropsychiatric disorders . here , we present a case report of a 24-year - old man , without a known psychiatric history , who developed brief psychotic symptoms following ingestion of small quantities of alcohol repeatedly . to our knowledge , no related previous literature regarding this has been reported .