Managing Anxiety in Heavy Cannabis Users

Primary Treatment Strategy: Cannabis Cessation

The primary treatment approach for patients with anxiety in the context of heavy cannabis use must be cannabis cessation, as cannabis itself likely exacerbates anxiety, according to the American College of Cardiology 1
Heavy cannabis use (>1.5 g/day inhaled, >20 mg/day THC oil, or >2-3 times daily of unknown content) is associated with worse psychiatric outcomes and may directly worsen anxiety symptoms, as reported by the British Journal of Anaesthesia 3, 1
Approximately 10% of chronic cannabis users develop cannabis use disorder characterized by clinically significant impairment, as stated by the American Psychiatric Association 1, 4

Cannabis inhibits CYP3A4, CYP2C19, and other cytochrome P450 enzymes that metabolize SSRIs, potentially increasing SSRI levels and adverse effects, according to the National Institute of Mental Health 2
Theoretical risk of serotonin syndrome exists when combining serotonergic medications with cannabis, as warned by the FDA 2
Benzodiazepines are used for acute cannabinoid hyperemesis syndrome management but carry high addiction risk, as reported by the Gastroenterology society 5
Amitriptyline 75-100 mg at bedtime is recommended for long-term management of cannabinoid hyperemesis syndrome, starting at 25 mg and titrating weekly, as suggested by the Gastroenterology society 5

Quantify daily intake: grams inhaled, mg THC/CBD in oils, or frequency if content unknown, as recommended by the British Journal of Anaesthesia 3
Engage in open, non-judgmental conversations about cannabis role in anxiety, as advised by the American Psychological Association 5, 1
Anticipate cannabis withdrawal syndrome in heavy users: anxiety, irritability, insomnia, decreased appetite, restlessness, as described by the British Journal of Anaesthesia 3
Consider tricyclic antidepressants (amitriptyline 25 mg titrated to 75-100 mg) for symptom management, as recommended by the Gastroenterology society 5

Cannabis use associates with myocardial infarction and stroke, particularly in older adults, as warned by the American Heart Association 1
Users have more than double the risk of motor vehicle accidents, with fatal accidents involving cannabis increasing from 9.0% (2000) to 21.5% (2018), as reported by the National Highway Traffic Safety Administration 1
Cannabis may exacerbate psychiatric disorders in vulnerable individuals, particularly with high-THC products, as stated by the American Psychiatric Association 1, 2
Long-term use causes cannabinoid hyperemesis syndrome (cyclic vomiting relieved by hot showers) requiring cannabis cessation, as described by the Gastroenterology society 5, 1