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Effects of chewing betel nut (Areca catechu) on the symptoms of people with schizophrenia in Palau, Micronesia

  • Roger J. Sullivan (a1), John S. Allen (a2), Caleb Otto (a3), Josepha Tiobech (a4) and Karen Nero (a1)...

Although millions of people with schizophrenia live in betel chewing regions, the effects of betel chewing on their symptoms are unknown. Betel nut alkaloids include potent muscarinic cholinomimetics: recent research suggests that these agents may be therapeutic in schizophrenia.


To compare the primary and extrapyramidal symptom profiles and substance-using habits of betel chewing v. non-chewing people with schizophrenia.


A cross-sectional study of 70 people with schizophrenia. Symptom ratings measured by the Positive and Negative Syndrome Scale (PANSS) and Extrapyramidal Symptom Rating Scale (ESRS), and demographic and substance-use data, were compared for 40 chewers and 30 non-chewers of betel nut.


Betel chewers with schizophrenia scored significantly lower on the positive (P=0.001) and negative (P=0.002) sub-scales of the PANSS than did non-chewers. There were no significant differences in extrapyramidal symptoms or tardive dyskinesia.


Betel chewing is associated with milder symptomatology and avoidance of more harmful recreational drugs. These initial results indicate that longitudinal research is merited.

Corresponding author
John S. Allen, Division of Cognitive Neuroscience & Behavioural Neurology, Department of Neurology – 2RCP, University of Iowa Hospitals & Clinics, Iowa City, IA 52242, USA
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Declaration of interest

Supported by grants from the University of Auckland Research Council and the New Zealand Schizophrenia Fellowship.

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  • ISSN: 0007-1250
  • EISSN: 1472-1465
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Effects of chewing betel nut (Areca catechu) on the symptoms of people with schizophrenia in Palau, Micronesia

  • Roger J. Sullivan (a1), John S. Allen (a2), Caleb Otto (a3), Josepha Tiobech (a4) and Karen Nero (a1)...
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