Caffeine-induced psychosis

While rare, caffeine-induced psychosis has been reported in both clinical studies and case reports. The Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition – Text Revision (DSM-5-TR) outlines five caffeine-related syndromes, including caffeine-induced anxiety disorder, caffeine-induced sleep disorder, and unspecified caffeine-related disorders, under stimulant-related diagnostic codes. The International Classification of Diseases, Tenth Revision (ICD-10) classifies disorders associated with caffeine more broadly, as "mental and behavioural disorders due to use of other stimulants, including caffeine". Several case studies and reviews have suggested that excessive caffeine intake may provoke psychotic or manic symptoms in vulnerable individuals. Caffeine may also worsen recovery in patients with bipolar disorder or pre-existing psychotic conditions, such as schizophrenia, which has led some clinical guidelines to recommend reducing or eliminating caffeine intake during psychiatric treatment, particularly for mania. Some case reports suggest that psychotic symptoms can emerge in individuals without a history of mental illness after consuming high doses of caffeine. Though not conclusively confirmed, it is hypothesized that caffeine may exacerbate underlying paranoid traits or lower the threshold for developing psychopathology in those predisposed to psychosis. Symptom resolution following caffeine discontinuation has been observed in several cases, supporting the existence of caffeine-induced psychosis. == Mechanisms ==

Caffeine acts as an antagonist of adenosine receptors, particularly A1 and A2A receptors. Under normal conditions, adenosine inhibits neurotransmission, which promotes sleep and suppresses arousal. By blocking these receptors, caffeine limits adenosine's inhibitory influence, which results in increased neuronal activity and the enhanced release of excitatory neurotransmitters, such as dopamine and glutamate. This mechanism contributes to improved alertness, attention, and mood at moderate doses. However, high doses or chronic overuse may overstimulate dopamine pathways in the brain, particularly in areas like the mesolimbic system, which are associated with the development of psychotic symptoms. The elevated dopaminergic activity resembles the neurochemical abnormalities observed in psychotic disorders to a lesser degree, and may trigger hallucinations, delusions, or manic symptoms, particularly in individuals who are genetically or biologically vulnerable. == Epidemiology ==

In healthy individuals Though a definitive causal relationship has not been established, caffeine's effect on dopamine levels may increase arousal and contribute to the onset of psychotic symptoms. Additionally, symptom improvement has been observed following caffeine reduction in individuals with pre-existing psychotic disorders. These findings suggest that individuals with a predisposition to psychosis may possess a lower threshold for developing psychopathological symptoms in response to caffeine intake. worsening the symptoms of schizophrenia. "Caffeine is metabolized by the CYP1A2 enzyme and also acts as a competitive inhibitor of this enzyme. Thus, caffeine can interact with a wide range of psychiatric medications, including antidepressant agents, antipsychotic agents, antimanic agents, antianxiety agents, and sedative agents." Consuming less than 250 mg of caffeine a day has been associated with better results on cognitive tasks in people with schizophrenia. However, more research still needs to be done to determine if the amount of caffeine that is safe to consume by people with schizophrenia (>250 mg/a day) is the same as that for the general population of people without schizophrenia. == References ==