psychiatry in internal medicine

1. “hard work is a misleading term. physical effort & long hours do not constitute hard
work. hard work is when someone pays you to do something you'd rather not be doing.
anytime you'd rather be doing something other than the thing you're doing...you're doing
hard work.”
― George Carlin
INTRODUCTION
● commonly used illegal psychoactive substance
● 9-tetrahydrocannabinol (THC)
Cannabis formulations
● Cannabis sativa
● contains > 60 known cannabinoids
● delta-9 tetrahydrocannabinol (THC) is the most psychoactive
● dried flower of the marijuana plant
PHARMACOLOGY
● Site of action
○ cannabinoid receptor is a GPCR
○ CB1
■ found in the CNS
■ inhibits release of several neurotransmitters
○ CB2
■ found peripherally in the immune system tissues
■ role in regulation of immune responses
● Pharmacokinetics
○ inhalation = rapid action (Effects felt at 15 to 30 minutes)
○ ingestion = has a delayed onset (1-2 hours)
○ THC is lipid soluble
○ highly protein-bound
○ Metabolised via CYP2C9 and 3A4
EPIDEMIOLOGY
● prevalence variable, as high as 5-10%
● young adults
Non nobis solum nati sumus
(​Not for ourselves alone are we born​)
-Dr. Eashan Srivastava

2. “hard work is a misleading term. physical effort & long hours do not constitute hard
work. hard work is when someone pays you to do something you'd rather not be doing.
anytime you'd rather be doing something other than the thing you're doing...you're doing
hard work.”
― George Carlin
● M>F
● College graduates have a lower prevalence
● Stressful conditions
○ Failing grades
○ Dislike of school
● who use alcohol, or cigarettes
● Unemployed
● Unmarried
PSYCHIATRIC COMORBIDITY
● Cannabis use and use disorder a/w high rates of comorbidity
○ alcohol use disorder
○ Smoking
○ opioid
○ mood disorders (depression, bipolar disorder)
○ schizophrenia
○ anxiety disorder
○ PTSD
○ OCD
○ ADHD
○ Antisocial personality disorder
ADVERSE EFFECTS OF CANNABIS USE
● Psychosocial functioning and health
○ A/W lower educational attainment
○ increased use of other drugs
● Brain structure and function
○ reduced hippocampal volume and lower hippocampal gray matter
● Neuropsychological effects
○ acutely impairs
Non nobis solum nati sumus
(​Not for ourselves alone are we born​)
-Dr. Eashan Srivastava

3. “hard work is a misleading term. physical effort & long hours do not constitute hard
work. hard work is when someone pays you to do something you'd rather not be doing.
anytime you'd rather be doing something other than the thing you're doing...you're doing
hard work.”
― George Carlin
■ Attention
■ Concentration
■ Memory
■ associative learning
● Cannabis-induced psychosis
○ in some users
○ Related to the development of schizophrenia associated with chronic cannabis
use
● Psychotic disorders
○ Schizophrenia
● Mood disorders
○ depression
○ Bipolar disorder
● Anxiety disorders
● Pulmonary
○ COPD
○ Cannabis smoke = carcinogen containing
● Cancer
○ Lung
○ Head and neck
● Cardiovascular
○ increases sympathetic activity and decreases parasympathetic activity
○ orthostatic hypotension
○ acute myocardial infarction
○ Stroke
● Reproductive
○ impaired spermatogenesis
○ Decreases prolactin levels
● Liver
○ acute hepatotoxicity
● Ophthalmologic
○ conjunctival vasodilation (red eyes)
Non nobis solum nati sumus
(​Not for ourselves alone are we born​)
-Dr. Eashan Srivastava

4. “hard work is a misleading term. physical effort & long hours do not constitute hard
work. hard work is when someone pays you to do something you'd rather not be doing.
anytime you'd rather be doing something other than the thing you're doing...you're doing
hard work.”
― George Carlin
○ decreased visual acuity
CANNABIS USE DISORDER
● DEFINITION
○ persisting pattern of cannabis use
○ results in clinically significant functional impairment in two or more domains
○ within a period of 12 months
○ Tolerance +
○ Withdarawl symptoms +
● C/F
○ impairment in school or work function
○ giving up of previously enjoyed social and recreational activities
○ use of cannabis in potentially hazardous situations, eg, while driving
○ episodic or chronic mood changes
○ thought disturbance
CANNABIS TOXICITY
● Children
○ Neurologic abnormalities are more prominent
○ Ataxia
○ excessive and purposeless motor activity of the extremities (hyperkinesis)
○ Lethargy
○ prolonged coma
○ sympathomimetic effects
○ Nausea, vomiting
Non nobis solum nati sumus
(​Not for ourselves alone are we born​)
-Dr. Eashan Srivastava

5. “hard work is a misleading term. physical effort & long hours do not constitute hard
work. hard work is when someone pays you to do something you'd rather not be doing.
anytime you'd rather be doing something other than the thing you're doing...you're doing
hard work.”
― George Carlin
● Adolescents and adults
○ Increased Pulse, BP
○ Increased respiratory rate
○ Conjunctival injection (red eye)
○ Dry mouth
○ Increased appetite
○ Nystagmus
○ Ataxia
○ Slurred speech
○ Mood, perception, thought content
■ Euphoria
■ decrease in anxiety, alertness
■ Perceptual changes include the sensation that colors are brighter and
music is more vivid
■ Time perception is distorted
■ Spatial perception can also be distorted
○ Cognition, psychomotor performance
■ slows reaction time
■ impairs attention, concentration, short term memory
■ Risk of accidents
● Complications associated with inhalation use
○ Acute exacerbations and poor symptom control in patients with asthma
○ Pneumomediastinum
○ pneumothorax
○ angina and myocardial infarction
Drug testing
● Urine
● Saliva
● Blood
○ THC Levels
Non nobis solum nati sumus
(​Not for ourselves alone are we born​)
-Dr. Eashan Srivastava

6. “hard work is a misleading term. physical effort & long hours do not constitute hard
work. hard work is when someone pays you to do something you'd rather not be doing.
anytime you'd rather be doing something other than the thing you're doing...you're doing
hard work.”
― George Carlin
MANAGEMENT
● consists of supportive care
● Maintain airway, breathing, and circulation
● supplemental oxygen
● intubation
● assisted ventilation
● exclude hypoglycemia
● Duration of coma is typically one to two days
● Mild dysphoria
○ Short-acting benzodiazepines
● R/o
○ BA
○ ACS
○ CVA
● GI decontamination
○ decontamination with activated charcoal
TREATMENT OF CANNABIS USE DISORDER
● P​sychosocial treatment
○ CBT
○ motivational enhancement therapy
○ counseling
○ Group therapy
○ Improve social skills
○ Improve social support and interpersonal functioning
○ Education about consequences of cannabis use
○ Mutual self help groups
■ Similar to Alcohol Anonymous
● PHARMACOTHERAPY
○ no medication is approved
Non nobis solum nati sumus
(​Not for ourselves alone are we born​)
-Dr. Eashan Srivastava

7. “hard work is a misleading term. physical effort & long hours do not constitute hard
work. hard work is when someone pays you to do something you'd rather not be doing.
anytime you'd rather be doing something other than the thing you're doing...you're doing
hard work.”
― George Carlin
○ N-acetylcysteine
■ mixed evidence of efficacy
○ gabapentin
○ Cannabinoid agonist
Non nobis solum nati sumus
(​Not for ourselves alone are we born​)
-Dr. Eashan Srivastava