Schizophrenia not only affects millions of people worldwide, but can be a complicated disease state to manage on a chronic basis.1-3  The DSM-IV-TR diagnostic manual presents schizophrenia as a major psychiatric disorder commonly associated with a various combination of symptoms that are categorized into being either positive, negative or disorganized symptoms.3  Positive symptoms include hallucinations and delusions, whereas negative symptoms include having a flat affect (no emotional expression), alogia (reduced thought and speech productivity), and avolition (decreased initiation of goal directed behavior).  Disorganized symptoms include disorganized speech, behavior, and poor attention.3  The approach to treatment of this disorder is currently centered around the modulation of the dopaminergic and serotonergic pathways in the central nervous system. 

It is also now well known across the general population that the use of complementary and/or alternative medicine is increasing for a number of medical conditions.  For example, in December 2008, the National Institutes of Health (NIH): National Center for Complementary and Alternative Medicine (NCCAM) and the National Center for Health Statistics (a division of the Centers for Disease Control and Prevention (CDC) surveyed 32,810 people for which their report showed that 38% of adults in the U.S. and nearly 12% of children (<17 years of age) used some form of complementary and/or alternative medicine.4  Of these forms of complementary and alternative medicines, natural products were ranked the greatest among these options at 17.7% and homeopathic treatments the least at 1.8% of the people sampled.4  As it relates to patients with psychiatric illness (including schizophrenia), it is now known that many of these patients will also use or seek after herbal or natural medicines to help treat their conditions.5-8  This may be especially true for paranoid patients who may believe that the "system" is trying to control them through the use of prescription medications.  Having an understanding of schizophrenia, it is plausible that some patients may feel better at determining their own treatment where they could seek the use of herbal or natural medicines without the knowledge or consent of you or the prescribing physician. 

Given the above information and its complexity, it would be important for clinicians to not only recognize this potential, but to also be able to recognize the utilization of some common herbal and natural medicines by their patients.  As such, a thorough medication use evaluation should be done at both clinic visits and admissions to the hospital. 

While this list is not exhaustive in nature, the following Chinese herbal products have been studied and used by patients with schizophrenia:9-12

• Dang gui cheng qi teng
• Ginkgo biloba standardized extract (EGb761)
• Hirudo seu Whitmania
• Radix Rhei palmatum
• Xiao yao san
• Xingshen

It is also important to recognize that many of these Chinese herbs are used in combination with normally prescribed antipsychotics and thus could contribute to unexpected variations in efficacy and/or safety profiles.8 

A systematic review by the Cochrane Collaboration was done to assess the impact of using herbal or natural medicines alone and in combination with standard antipsychotics on psychotic symptoms, global functioning and development of adverse effects.13  While this review only included 6 studies that had small sample sizes and were of short duration, they reported that these herbal medicines should not be used alone to treat psychotic symptoms, but could be beneficial when used in combination with traditional antipsychotics as it relates to the patients mental state, global functioning and decreasing adverse effects.  While this may appear to be promising findings, it is important to recognize that these findings would need to be validated through additional studies.

References:

1. National Alliance of Mental Illness.  Schizophrenia.  February 2007.  Last accessed on 8/3/2009.  
2. Schizophrenia Society of Canada.  What is Schizophrenia?  An Information Guide.  Last accessed 8/3/2009.  
3. American Psychiatric Society.  Practice Guideline for the Treatment of Patients with Schizophrenia Second Edition.  Last accessed on 8/3/2009.  
4. National Center for Complementary and Alternative Medicine: National Institutes of Health.  The Use of complementary and alternative medicine in the United States: 2007 National Health Interview Survey Report.  Last accessed on 1-17-2009.  
5. Druss BG, Rohrbaugh R, Kosten T et al.  Use of alternative medicine in major depression.  Pscyhiatr Serv  1998;49:1397.  
6. Davidson JR, Rampes H, Eisen M et al.  Psychiatric disorders in primary care patients receiving complementary medical treatments.  Compr Psychiatry  1998;39:16-20.  
7. Unutzer J, Klap R, Sturm R et al.  Mental disorders and the use of alternative medicine: results from a national survey.  Am J Psychiatry  2000;157:1851-7. 
8. Matthews SC, Camacho A, Lawson K et al.  Use of herbal medications among 200 psychiatric outpatients: prevalence, patterns of use, and potential dangers.  Gen Hosp Psychiatry  2003;25:24-6.  
9. Zhang LD, Tang YH, Zhu WB et al.  Comparative study of schizophrenia treatment with electroacupuncture, herbs and chlorpromazine.  Chin Med J (Engl)  1987;100:152-7.  
10. Meng FQ, Cui YH, Wang SH.  A double-blind placebo controlled study of EGb761 in the treatment of chronic schizophrenia.  1996;6:339-41.  [Not in PubMed].
11. Zhang XY, Zhou DF, Zhang PY et al.  A double-blind, placebo controlled trial of extract of Glinkgo biloba added to haloperidol in treatment-resistant patients with schizophrenia.  J Clin Psychiatry  2001;62:878-83.  
12. Zhu YZ, Kang B, Zhu QQ.  Clinical study of shuizhi-dahuang mixture in treating schizophrenics with blood stasis syndrome.  Zhongguo Zhong Xi Yi Jie He Za Zhi 1996;16:646-8.  
13. Rathbone J, Zhang L, Zhang M et al.  Chinese herbal medicine for schizophrenia: Cochrane systematic review of randomized trials.  Br J Psychiatry  2007;190:379-84.

Schizophrenia, Natural Medicines, Herbal Medicines, Herbs Used Schizophrenia