New onset psychosis following cannabis discontinuation: A case report

Substance-induced psychoses are brief psychotic syndromes triggered by substance use that can persist for days to weeks after substance discontinuation. With the rising popularity of cannabis and cannabis-related products, including synthetic cannabinoids, the incidence of cannabis-related psychotic episodes may continue to rise, particularly among geriatric populations where less is known about cannabis effects on psychotic symptoms. This case study examines the emergence of psychotic symptoms following abrupt cannabis cessation in a 67-year-old female with pre-existing anxiety and depression. A 67-year-old Caucasian female developed new-onset paranoid delusions and suicidal ideation approximately four weeks after discontinuing six years of heavy cannabis use (3 grams daily). She required two hospitalizations with treatment including risperidone (Risperdal) and escitalopram. Complete resolution of psychotic symptoms occurred with short-term antipsychotic treatment, which was successfully discontinued after four months. This case contributes to growing evidence suggesting a potential link between cannabis withdrawal and new-onset psychosis, among vulnerable populations with underlying mental health conditions. The successful resolution with short-term treatment and absence of recurrence after medication discontinuation highlights the temporary nature of this phenomenon.