223 - References

References

222 The Maudsley® Prescribing Guidelines in Psychiatry CHAPTER 1 Other options include adding pimozide, olanzapine or sertindole. None is recommended: pimozide and sertindole have important cardiac toxicity and the addition of olanzapine is poorly supported96 and likely to exacerbate metabolic adverse effects. Studies of pimozide97,98 and sertindole99 have shown no effect. One small RCT supports the use of Ginkgo biloba100 and another two support the use of memantine.101,102 Another study suggests possible benefit of augmentation with acetyl-­L-­carnitine103 and a case study reports good outcome with thyroxine.104 A single RCT describes successful use of sodium benzoate.105 Minocycline is probably not effective.77,106 Glycine may be effective for positive symptoms, but studies are of poor quality.107 A small case series (n = 6) found benefit from adding pimavanserin.108 N-­acetylcysteine is probably of no benefit.109–111 References

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