Cannabis Pen-Induced Psychosisin a First-Time Adolescent User

Abstract

Cannabis is a widely used illicit substance that is historically consumed via smoking, but alternative methods of cannabis consumption have been growing in popularity over the past several decades. One such modality is vaporization, which can appeal specifically to adolescent consumers given these pen devices’ ease of concealment, lack of characteristic odor, and marketability. Cannabis products designed for vaping often have higher concentrations of the psychoactive component of cannabis, tetrahydrocannabinol (THC), when compared with traditional cannabis leaf smoking. This can increase the intensity of cannabis-related effects such as analgesia, relaxation, appetite stimulation, and reduced nausea and emesis, but also potentially increases the risk for adverse effects such as dysphoria, and more severely, cannabis-induced psychosis (CIP). Here, we present the case of an adolescent female who was brought after school to our emergency department presenting with symptoms of acute psychosis. Her subsequent workup was effectively normal apart from a urine drug screen positive for THC, which the patient confirmed was due to use of a cannabis pen prior to leaving school that day. This prompted the diagnosis of CIP, which was self-limited and resolved without significant intervention. We use this case to provide the symptomatology and treatment of CIP secondary to cannabis pen use, as well as more broadly discuss the potential implications of cannabis vaping on adolescent neurodevelopment, substance use, and psychiatric comorbidities.

Case History

An adolescent female with no significant past medical history was brought to the emergency department (ED) by her mother over concerns of substance use at school and self-injurious behaviors. The patient had been picked up from the bus stop by her mother, who noticed the patient was disoriented, believing that she had just returned from her babysitting job. Her mother was concerned she might have taken something, and further questioning revealed that the patient had used a “weed pen” supplied by a peer. To the mother’s knowledge, this was her daughter’s first time using cannabis, but she did have a history of nicotine vaping for several months and family history was significant for alcohol use disorder in her father. During the car ride, the patient became more disoriented and made comments that she had recently cut herself deliberately. The patient had a history of a prior suicide attempt by strangulation two years prior and had seen a therapist for several sessions before being lost to follow up. She never received a formal psychiatric diagnosis, but family history was significant for major depressive disorder in her mother. Significant change in baseline orientation and concern for suicidal ideation recurrence prompted her mother to take her to the ED.

Symptomatology

At the time of ED admission, the patient was oriented to person, but orientation to place and time fluctuated initially. She was able to answer questions, but often her answers were tangential and disorganized, and she would laugh inappropriately. There was no evidence of auditory/visual hallucinations or responses to internal stimuli; however, she did mention vague visual hallucinations after initially using the cannabis pen. She also exhibited labile emotions and erratic behaviors consistent with paranoia that were especially prominent during the car ride to the ED per her mother, but she did not exhibit signs of anger or aggression. Physical examination was without abnormality apart from mild tachycardia, including absent conjunctival injection, nystagmus, or gait abnormalities. This presentation was determined to be most consistent with acute psychosis.

Diagnosis

Many possible causes of acute psychosis in an adolescent were considered in the ED. The patient was mildly tachycardic, but afebrile without tachypnea, or leukocytosis, effectively ruling out septic encephalopathy. Oxygen saturation and respiratory rate were within normal limits, suggesting against hypoxia-induced delirium. Complete metabolic panel was grossly normal, ruling out possible etiologies such as electrolyte imbalance, hypo- or hyperglycemia, and uremic or hepatic encephalopathy. Grossly normal vitals, blood chemistries, and thyroid stimulating hormone levels ruled out endocrine dysfunction such as Cushing syndrome or thyroid disease. From a pure psychiatric perspective, the patient did not meet criteria for any psychotic disorders given the short duration of symptoms, although the initial stage of brief psychotic disorder was initially considered on the differential. Urine drug screen collected at the time of ED admission was positive for THC, but negative for other substances such as cocaine, amphetamines, phencyclidine, opiates, benzodiazepines, or alcohol. There was concern that the patient’s tachycardia was the result of a possible drug overdose given her expressed suicidal ideation. As such, salicylate and acetaminophen blood levels were measured and undetectable. There were no abnormalities on electrocardiogram or chest x-ray. Head imaging was not indicated given the lack of trauma history or neurologic deficits on exam. Given history, physical, and laboratory results, cannabis-induced psychosis (CIP) was considered the most likely diagnosis.

Treatment

The patient was given supportive care and intravenous fluids and monitored for return to baseline mentation. Over the course of three hours, the patient’s hallucinations and paranoia improved significantly and resolved. Thoughts of self-harm combined with drug-induced psychotic episode met inpatient criteria, and she was admitted to our hospital for crisis stabilization and further management. Upon admission, she reported persistent depressed mood, poor sleep, low energy, poor concentration, and feelings of worthlessness over the past year, consistent with major depressive disorder. She also confirmed intermittent past episodes of self-injurious behavior by cutting without suicidal intent to mitigate low mood, as well as anxiety especially in social situations. The patient stated that pressures to perform in school and athletic pursuits were contributing factors to her poor mental health. The patient denied using cannabis prior to the event resulting in admission. She stated she was a disappointment to her parents and felt responsible for their strained relationship. The patient was administered multiple screening questionnaires, which were positive for moderate depression and multiple anxiety disorders including generalized anxiety disorder, social anxiety disorder, and panic attacks. The patient, family, and team agreed to a trial of escitalopram. The importance of combination with cognitive behavioral therapy was also stressed, and the patient re-established contact with her prior therapist for outpatient follow-up. Throughout her admission, the patient attended individual and group therapy sessions with willing participation, focusing on skills to manage emotions, cognitive-behavioral skills, social skills, and stress coping strategies. Risks of cannabis use were communicated to the patient and abstinence was encouraged. A productive family meeting was held focused on discussing ways to improve communication to mitigate the patient’s triggers. Due to consistent improvement in symptoms without any thoughts of harming self, the patient was discharged home with a plan to follow up with psychiatry and her therapist outpatient.

Discussion

Cannabis use and vaping are growing in adolescents, with adverse events like CIP likely to increase as well. THC concentration is thought to be directly related with risk of CIP, and cannabis vape products often have much higher THC concentrations than those that are smoked.¹ Nonetheless, even at the same dose, vaporization leads to higher blood THC concentrations and greater pharmacodynamic effects than smoking,² suggesting that cannabis vaping confers a greater risk of CIP than smoking even in first-time users. Thus, our case highlights the concerns of cannabis vaping compared to cannabis smoking. While our patient’s symptoms were relatively mild and self-limited, CIP can present with more prolonged or severe symptoms that require pharmacological intervention. Although there is no standard treatment for CIP, some prior cases report varying levels of symptomatic control with second-generation antipsychotics such as olanzapine or lurasidone, as well as anti-epileptics with mood stabilizing effects such as valproic acid or carbamazepine.^3–5 Following recovery from CIP, patients should be encouraged to abstain from further cannabis use as the most definite strategy to prevent further episodes.

Part of counseling adolescents and their parents should include the possible impact of cannabis use on their neurodevelopment. The cannabinoid system is thought to play an important role in synapse formation. Adults who regularly used cannabis during adolescence demonstrated lower neural connectivity of regions critical for learning and memory such as the hippocampus, prefrontal cortex, subcortical networks, and precuneus.⁶ As such, cannabis use in adolescence is associated with lower educational attainment and IQ and even impaired development of psychomotor skills necessary for driving.^7–9 In educating patients and their families, it is important to note that these neurochemical changes are not irreversible, but rather, approximately four weeks of abstinence can grossly normalize brain function.¹⁰ While the above findings again support a role for abstinence, they also suggest that cannabis vaping would further exacerbate deficits in neurodevelopment through exposure to greater THC concentrations.

This case also highlighted substance use as a stress coping mechanism. Our patient expressed academic, athletic, and relational stressors, while also struggling with depression and anxiety. To cope with this, it is important to note that this was not the first instance of her turning to substances, as she had already been vaping nicotine with relative consistency. The literature demonstrates a strong relationship between vaping of one substance and a higher probability of vaping another, especially between nicotine and cannabis.^11,12 While cannabis can be acutely anxiolytic, frequent use of THC products can be associated with increased feelings of anxiety and panic¹³ and may also be associated with depression and self-harm.¹⁴ The case of adolescent CIP presented above highlights the need for proper education of adolescents regarding adverse acute effects of cannabis, as well as negative chronic effects on neurodevelopment, while also encouraging adolescents to develop healthier and more durable coping mechanisms.