Drug misuse, intoxication and withdrawal: Hallucinogens: Pathology review

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Drug misuse, intoxication and withdrawal: Hallucinogens: Pathology review

Psychological disorders

Mood disorders

Major depressive disorder


Bipolar disorder

Seasonal affective disorder

Premenstrual dysphoric disorder

Anxiety disorders

Generalized anxiety disorder

Social anxiety disorder

Panic disorder



Obsessive-compulsive disorders

Obsessive-compulsive disorder

Body focused repetitive disorders

Body dysmorphic disorder

Stress-related disorders and abuse

Post-traumatic stress disorder

Physical and sexual abuse

Psychotic disorders

Schizoaffective disorder

Schizophreniform disorder

Delusional disorder


Cognitive and dissociative disorders



Dissociative disorders

Eating disorders

Anorexia nervosa

Bulimia nervosa

Personality disorders

Cluster A personality disorders

Cluster B personality disorders

Cluster C personality disorders

Somatoform and factitious disorders

Somatic symptom disorder

Factitious disorder

Substance use disorders and drugs of abuse

Tobacco dependence

Opioid dependence

Cannabis dependence

Cocaine dependence

Alcohol use disorder

Sleep disorders


Nocturnal enuresis


Night terrors

Narcolepsy (NORD)

Sexual dysfunction disorders

Erectile dysfunction

Male hypoactive sexual desire disorder

Orgasmic dysfunction

Female sexual interest and arousal disorder

Genito-pelvic pain and penetration disorder

Pediatric disorders

Attention deficit hyperactivity disorder

Disruptive, impulse control, and conduct disorders

Learning disability

Fetal alcohol syndrome

Tourette syndrome

Autism spectrum disorder

Rett syndrome

Shaken baby syndrome



Psychiatric emergencies


Serotonin syndrome

Neuroleptic malignant syndrome

Psychological disorders review

Mood disorders: Pathology review

Amnesia, dissociative disorders and delirium: Pathology review

Personality disorders: Pathology review

Eating disorders: Pathology review

Psychological sleep disorders: Pathology review

Psychiatric emergencies: Pathology review

Drug misuse, intoxication and withdrawal: Hallucinogens: Pathology review

Malingering, factitious disorders and somatoform disorders: Pathology review

Anxiety disorders, phobias and stress-related disorders: Pathology Review

Trauma- and stress-related disorders: Pathology review

Schizophrenia spectrum disorders: Pathology review

Drug misuse, intoxication and withdrawal: Stimulants: Pathology review

Drug misuse, intoxication and withdrawal: Alcohol: Pathology review

Developmental and learning disorders: Pathology review

Childhood and early-onset psychological disorders: Pathology review


Drug misuse, intoxication and withdrawal: Hallucinogens: Pathology review

USMLE® Step 1 questions

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USMLE® Step 1 style questions USMLE

of complete

A 24-year old man is brought to the emergency department by the police after being found wandering the streets screaming at bystanders. He resisted arrest and became physically aggressive. While a nurse attempts to place an IV, the patient screams and attempts to hit her. His temperature is 37.1°C (98.6°F), respirations are 20/minute, heart rate is 120/minute, and blood pressure is 155/95 mmHg. The patient is subsequently provided with intramuscular haloperidol. Urine toxicology confirms the use of a drug that exerts its effects by binding to and activating N-methyl-D-aspartate (NMDA) receptors. Which of the following physical exam findings is highly associated with this drug?


Content Reviewers

Antonia Syrnioti, MD


Antonella Melani, MD

Evan Debevec-McKenney

Talia Ingram, MSMI, CMI

In the middle of the night, two people are brought to the clinic. First comes 18 year old Kyle and his mother, who's noticed that lately, Kyle seems to have an increased appetite, and won’t stop laughing or giggling. Kyle adds that he feels like time has stopped and that’s making him a bit anxious. Upon physical examination, Kyle’s eyes are extremely red, he has a heart rate of 105 beats per minute, and a blood pressure of 130 over 90 millimeters of mercury. Next comes 25 year old Matt and his girlfriend Allison, who is very concerned for him. She says that in the past few months, Matt has been very aggressive and violent, and has been frequently getting into fights with strangers for no good reason. Matt interrupts Allyson and tells you that the reason he gets into fights is because some voices in his head tell him so. Upon physical examination, you notice that Matt keeps tapping his feet, and his eyes keep moving from side to side and up and down. In addition, he has a heart rate of 110 beats per minute, and a blood pressure or 135 over 95 millimeters of mercury.

Based on the initial presentation, both Kyle and Matt seem to have some form of hallucinogen intoxication. Hallucinogens are a class of psychoactive drugs that cause hallucinations, which are distortions of a person’s sensory perception, mood, and thought, as well as enhancement of feelings and introspection. The way they do this isn’t clearly understood, but it involves the interaction of numerous neurotransmitters, including serotonin, dopamine, and glutamate. Now, some high yield hallucinogens include lysergic acid diethylamide or LSD, cannabis or marijuana, MDMA or ecstasy, and phencyclidine or PCP. And in addition to causing hallucinations, they can all cause their own set of unique symptoms that you need to be able to recognize for your exams. In addition to these, they can all cause their own set of unique symptoms that you need to be able to recognize for your exams.


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