Schizophrenia & Caffeine

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Most people consider caffeine to be a relatively harmless drug. In fact, many people might not even consider caffeine to be a drug at all. However, caffeine can cause a host of mental and physical problems when consumed in excess. According to a review published in 2005 in the journal "Advances in Psychiatric Treatment," most practitioners don't ask about caffeine intake when performing psychiatric assessments, despite the fact that caffeine may exacerbate psychotic and other psychiatric symptoms.

About Schizophrenia

Schizophrenia is a chronic, debilitating mental health disorder that affects around 2.4 million Americans, according to the 2005 National Comorbidity Survey-Replication. Symptoms of schizophrenia can range from mild to severe, involving delusions and hallucinations. People with schizophrenia generally suffer from thought disorder, meaning that they have trouble organizing and putting their thoughts into words. They also tend to exhibit inappropriate, child-like behaviors or extreme agitation, and often withdraw socially. Schizophrenia also causes emotional flatness, meaning that patients have little or no interest in regular activities. People with schizophrenia may neglect personal hygiene, forgetting to shower or bathe for days or weeks. Sometimes, schizophrenia can result in symptoms of depression or mood swings. Because it is a chronic, incurable disease, patients must rely on medication for symptom relief and management. However, many patients do not want to take medication because of their serious, although rare, side effects. Psychotherapy and social interventions may also be beneficial for schizophrenics.

Effects of Caffeine

For most people, a moderate intake of caffeine is generally considered safe. According to Teen's Health, this means an intake of around 200 to 300 mg of caffeine daily. An average cup of coffee contains around 115 mg of caffeine. In moderate amounts, caffeine may help alleviate mental fatigue and provide a brief energy boost. Ingesting too much caffeine can lead to a condition known as caffeinism. The authors of the review from the journal "Advances in Psychiatric Treatment" point out that caffeinism can lead to symptoms of restlessness, agitation, excitement, rambling thought and speech, and insomnia, many symptoms that are consistent with those of schizophrenia and other psychiatric disorders. This does not imply that caffeine causes schizophrenia but merely suggests that ingesting too much caffeine may trigger or worsen certain symptoms.

Clinical Evidence

Several clinical studies have shown that increased caffeine consumption can exacerbate schizophrenic symptoms. A case study published in the September 1978 issue of the "Journal of Clinical Psychiatry" showed that increased caffeine consumption caused a significant increase in schizophrenic symptoms. Another study, published in the July 1990 issue of the journal "Biological Psychiatry" confirmed that, when compared with a placebo, caffeine caused a significant increase in manic symptoms, thought disorder, unusual thought content and euphoria-activation in schizophrenic patients. Additionally, a study published in the September 2006 issue of "Schizophrenia Research" confirmed that people with schizophrenia smoke more and have a higher intake of caffeine when compared with the general U.S. population.


While caffeine may increase schizophrenic symptoms, it is interesting to note the high number of schizophrenics who rely heavily on caffeine. A review published in the November 1998 issue of "Psychiatric Services," a journal of the American Psychiatric Association, suggests that schizophrenic patients may use high levels of caffeine in an attempt to self-medicate or alleviate boredom. The authors also state that patients may use caffeine to combat the sedative effects of certain medications. Additionally, they point out that many schizophrenics smoke. As smoking causes an increased elimination of caffeine, schizophrenics may require increasingly higher amounts of caffeine to achieve the same effects. The authors of the study published in "Schizophrenia Research" suggest that clinicians should employ lifestyle modification counseling in addition to other treatment modalities when working with patients with schizophrenia to address smoking and caffeine intake.