Aims – to present the use of glycine and its analogues (D-serine and D-cycloserine) in the treatment of schizophrenia, in order to normalize neurotransmission within the glutamatergic system. Moreover, available research results are presented concerning administration of these substances in addition to various neuroleptics, as well as efficacy and safety of such therapy.
Review – Glycine as a co-modulator of glutamatergic NMDA receptor is necessary for its normal functioning. It is assumed that adjunctive glycine in neuroleptic treatment should result in all amelioration of transmission within the glutamatergic system and in consequence– in symptom relief in schizophrenia.
Conclusions – A majority of presented studies indicate beneficial effects of glycine, D-serine and D-cycloserine in schizophrenic patients, especially as regards negative symptoms. Such outcomes was reported particularly when these substances had been added to classical and atypical neuroleptics (except for clozapine). No favourable effects were obtained in clozapine adjuvant therapy, which may be due to a supposed direct action of this medication on NMDA receptor, and to its rivalry with glycine for receptor sites. Safety of the treatment with glycine and its analogues is emphasized.