Most medications used for schizophrenia are in the
family. The atypical antipsychotics are so called because they are chemically quite different.
They appear to cause fewer side effects than the phenothiazine drugs
Medications in this family include:
- Olanzapine (Zyprexa)
- Risperidone (Risperdal)
- Clozapine (Clozaril)
- Quetiapine (Seroquel)
- Ziprasidone (Geodon)
- Aripiprazole (Abilify)
St. John's Wort
The herb St. John’s wort might reduce levels of these medications in the blood.
This could lead to an increase in the severity of psychotic symptoms.
Perhaps even more dangerously, if medication levels are adjusted for an individual already taking St. John’s wort, stopping the herb could cause these levels to rise, potentially causing dangerous toxic symptoms.
A few studies suggest that the amino acid glycine may augment the action of phenothiazine antipsychotic drugs. It might also augment the action of olanzapine and risperidone, but whether it augments or decreases the effectiveness of clozapine remains unclear.
article for a more detailed discussion of this subject.
Highly preliminary evidence suggests that ginkgo might reduce the side effects and increase the efficacy of various antipsychotic medications, including atypical antipsychotic drugs.
De Smet PA and Touw DJ. Safety of St. John's wort.
Liu P, Luo HC, Shen YC, et al. Combined use of
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Potkin SG, Jin Y, Bunney BG, et al. Effect of clozapine and adjunctive high-dose glycine in treatment-resistant schizophrenia.
Am J Psychiatry
Evins AE, Fitzgerald SM, Wine L, et al. Placebo-controlled trial of glycine added to clozapine in schizophrenia.
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Diaz P, Bhaskara S, Dursun SM, et al. Double-blind, placebo-controlled, crossover trial of clozapine plus glycine in refractory schizophrenia negative results.
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Am J Psychiatry.