all information


Principal Proposed Natural Treatments
  • Glycine
Herbs and Supplements to Avoid
  • Chromium Picolinate, Dong Quai, Kava, Phenylalanine, St. John’s Wort, Yohimbe

Schizophrenia is a chronic, severe, disabling brain disease. People with schizophrenia often suffer terrifying symptoms, such as hearing internal voices not heard by others, or believing that other people are reading their minds, controlling their thoughts, or plotting to harm them. These symptoms may leave them fearful and withdrawn. Their speech and behavior can be so disorganized that they may be incomprehensible or frightening to others. Schizophrenia increases a person’s risk of suicide, self-mutilation, substance abuse, and other social problems such as unemployment, homelessness, and incarceration.

Schizophrenia is found all over the world. The severity of the symptoms and the long-lasting, chronic pattern of schizophrenia often cause a high degree of disability. Approximately 1% of the population develops this condition during their lifetime; more than 2 million Americans suffer from the illness in a given year. Although schizophrenia affects men and women with equal frequency, the disorder often appears earlier in men. Men are usually affected in their late teens or early twenties, while women are generally affected in their twenties to early thirties.

Researchers aren’t sure what causes schizophrenia. Problems with brain structure and chemistry are thought to play a role. There appears to be a strong genetic component, but some researchers believe that environmental factors may contribute. They theorize that a viral infection in infancy and/or extreme stress may trigger schizophrenia in people who are predisposed to it.

Conventional drug treatment for schizophrenia is moderately effective. While it seldom produces a true cure, it can enable a person with schizophrenia to function in society.

Principal Proposed Natural Treatments

Untreated schizophrenia is a very dangerous disease for which there is effective treatment, and for this reason it is not ethical to perform studies that compare a hypothetical new treatment against placebo. Therefore, studies of natural treatments for schizophrenia have looked at their potential benefit for enhancing the effects of standard treatment (or minimizing its side effects). No natural treatments have been studied as sole therapy for schizophrenia.


Up until recently, all common medications used for schizophrenia fell into a class called phenothiazines . These drugs are most effective for the "positive" symptoms of schizophrenia, such as hallucinations and delusions. (Such symptoms are called "positive" because they indicate the presence of abnormal mental functions, rather than the absence of normal mental functions.) In general, however, these medications are less helpful for the "negative" symptoms of schizophrenia, such as apathy, depression, and social withdrawal.

The supplement glycine might be of benefit here. A clinical trial enrolled 22 participants who continued to experience negative symptoms of schizophrenia despite standard therapy. 1 In this double-blind, placebo-controlled crossover study, volunteers were randomly assigned to receive either 0.8 g of glycine per kg of body weight (about 60 g per day) or placebo for 6 weeks, along with their regular medications. The groups were then switched after a 2-week "wash-out" period during which they all received placebo.

Significant improvements (about 30%) in symptoms such as depression and apathy were seen with glycine when compared to placebo. Additionally, glycine appeared to reduce some of the side effects caused by the prescription drugs. Furthermore, the benefits apparently continued for another 8 weeks after glycine was discontinued.

No changes were seen in positive symptoms (for instance, hallucinations), but it isn’t possible to tell whether that is because these symptoms were already being controlled by prescription medications or whether glycine simply has no effect on that aspect of schizophrenia.

Four other small double-blind, placebo-controlled clinical trials of glycine together with standard drugs for schizophrenia (including the newer drugs olanzapine and risperidone) also found it to be helpful for negative symptoms. 1-4

However, one small double-blind, placebo-controlled trial (19 participants) suggests that adding glycine to the drug clozapine may not be a good idea. 5 In this study, glycine was found to reduce the benefits of clozapine without helping to relieve the participants' negative symptoms. Lack of benefit, although no actual harm, was seen in two other double-blind, placebo-controlled trials of glycine and clozapine.6,37 Another recent study not specifically limited to clozapine also failed to find benefit with glycine.43

Curiously, a natural substance (sarcosine) that blocks the action of glycine has also shown promise for schizophrenia. 34

For more information, including dosage and safety issues, see the full Glycine article.

Other Proposed Natural Treatments

Numerous other natural therapies have shown promise for aiding various aspects of treatment for schizophrenia, but, in most cases, the current supporting evidence is weak at best.

Enhancing Drug Action

For a number of theoretical reasons, it has been suggested that fish oil and its constituents (especially a slightly modified constituent called ethyl-EPA) might enhance the effectiveness of standard drugs used for schizophrenia; however, current evidence for benefit remains incomplete and inconsistent.35,42

A small 6-week, double-blind, placebo-controlled study evaluated the potential effectiveness of the supplement dehydroepiandrosterone (DHEA) taken at a dose of 100 mg daily for enhancing the effectiveness of drug treatment for schizophrenia. 33 The results indicated that use of DHEA led to improvement in various symptoms, especially negative symptoms. However, in another double-blind, placebo-controlled study, use of DHEA provided minimal benefits if any. 40

Preliminary evidence suggests that ginkgo7,8, the amino acid D-serine,9 and N-acetyl cysteine44 may also enhance the effectiveness of various antipsychotic drugs.

Tardive Dyskinesia

Tardive dyskinesia (TD) is a potentially permanent side effect of drugs used to control schizophrenia and other psychoses. This late-developing (tardy, or tardive) complication consists of annoying, mostly uncontrollable movements (dyskinesias). Typical symptoms include repetitive sucking or blinking, slow twisting of the hands, or other movements of the face and limbs. TD can cause tremendous social embarrassment.

Several natural treatments have shown promise for preventing or treating TD. For more information, see the Tardive Dyskinesia article.

Other Drug Side Effects

Vitamin B6 might also reduce symptoms of akathesia, a type of restlessness associated with phenothiazine antipsychotics. 38

One small double-blind study found that use of DHEA reduced the Parkinson-like movement disorders that may occur in people taking phenothiazine drugs. 39

According to studies performed in China, the herb ginkgo may reduce various side effects caused by drugs used to treat schizophrenia. 7,13

Preliminary studies suggest that phenothiazine drugs might deplete the body of coenzyme Q10 (CoQ10).13,14 While there is as yet no evidence that taking this supplement provides any specific benefit for people using phenothiazines, supplementing with CoQ10 might be a good idea on general principles.

The herb milk thistle might protect against the liver toxicity sometimes caused by phenothiazine drugs. 15

Other Options

Preliminary evidence suggests that a special form of magnet therapy called repetitive transcranial magnetic stimulation (rTMS) may be useful for schizophrenia.16,17 However, not all studies have found benefits above the placebo effect;36 rTMS is not yet available outside a research setting.

A study of 19 people with schizophrenia who had disturbed sleep patterns found that 2 mg of controlled-release melatonin improved sleep. 18

One small study failed to find the supplement creatine helpful for schizophrenia. 41

High doses of various vitamins, including folate, vitamin A , vitamin B1 , vitamin B3 (niacin) , vitamin B6 , vitamin B12, vitamin C, and vitamin E have been suggested for the treatment of schizophrenia, but the evidence that they offer any real benefit remains incomplete and contradictory at best. 19-26

Herbs and Supplements to Avoid

There are some indications that using the supplement phenylalanine while taking antipsychotic drugs might increase the risk of developing tardive dyskinesia. 27,28

Antipsychotic drugs can cause dystonic reactions—sudden intense movements, and prolonged muscle contraction of the neck and eyes. There is some evidence that the herb kava can increase the risk or severity of this side effect. 29

Phenothiazine drugs can cause increased sensitivity to the sun. Various herbs, including St. John's wort and dong quai , can also cause this problem. Combined treatment with herb and drug might increase the risk further.

St. John’s wort might also interact adversely with the newer antipsychotic drugs in the clozapine family. If you take one of these drugs and then start taking St. John’s wort, your blood levels of the drug may fall. However, if you are already taking both the herb and the drug, and then you stop St. John’s wort, the level of drug in your body could reach the toxic point.

The supplement chromium is often sold in the form chromium picolinate . Because picolinate can alter levels of various neurotransmitters (substances that the brain uses to function), there are theoretical concerns that it could cause problems for people with schizophrenia. 30,31

The herb yohimbe is relatively toxic and can cause problems if used incorrectly. Phenothiazine medications may increase the risk of this toxicity. 32


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Last reviewed May 2008 by EBSCO CAM Review Board

Please be aware that this information is provided to supplement the care provided by your physician. It is neither intended nor implied to be a substitute for professional medical advice. CALL YOUR HEALTHCARE PROVIDER IMMEDIATELY IF YOU THINK YOU MAY HAVE A MEDICAL EMERGENCY. Always seek the advice of your physician or other qualified health provider prior to starting any new treatment or with any questions you may have regarding a medical condition.