Non-neuroleptic approaches to treating negative symptoms in schizophrenia.

The novel/atypical neuroleptics have proven to be effective in treating negative symptoms but although clinical experience appears to show that they have advantages over the traditional neuroleptics in treating negative symptoms, superiority has not always been statistically confirmed and the treatment results in individual patients in everyday clinical practice are often not satisfying. Therefore other drug treatment options also have to be carefully considered. This paper presents a systematic review of non-neuroleptic drug treatments for negative symptoms in schizophrenia, based on MEDLINE searches in the databases from 1995 to September 2002 to identify pertinent clinical trials. Relevant literature was also found in the reference lists of papers identified by the MEDLINE searches. Most of the alternatives to neuroleptics have only been investigated as add-on therapies and not as monotherapies. The SSRIs seem to have a certain place in the treatment of negative symptoms. Anticonvulsants, oestrogens and glutamatergic drugs can currently only be seen as experimental drugs and require further empirical evaluation.