L-lysine as adjunctive treatment in patients with schizophrenia: a single-blinded, randomized, cross-over pilot study.

BACKGROUND: Accumulating evidence suggests that the brain's nitric oxide (NO) signalling system may be involved in the pathophysiology of schizophrenia and could thus constitute a novel treatment target. The study was designed to investigate the benefit of L-lysine, an amino acid that interferes with NO production, as an add-on treatment for schizophrenia. METHODS: L-lysine, 6 g/day, was administered to 10 patients with schizophrenia as an adjunctive to their conventional antipsychotic medication. The study was designed as a single-blinded, cross-over study where patients were randomly assigned to initial treatment with either L-lysine or placebo and screened at baseline, after four weeks when treatment was crossed over, and after eight weeks. RESULTS: L-lysine treatment caused a significant increase in blood concentration of L-lysine and was well tolerated. A significant decrease in positive symptom severity, measured by the Positive And Negative Syndrome Scale (PANSS), was detected. A certain decrease in score was also observed during placebo treatment and the effects on PANSS could not unequivocally be assigned to the L-lysine treatment. Furthermore, performance on the Wisconsin Card Sorting Test was significantly improved compared to baseline, an effect probably biased by training. Subjective reports from three of the patients indicated decreased symptom severity and enhanced cognitive functioning. CONCLUSIONS: Four-week L-lysine treatment of 6 g/day caused a significant increase in blood concentration of L-lysine that was well tolerated. Patients showed a significant decrease in positive symptoms as assessed by PANSS in addition to self-reported symptom improvement by three patients. The NO-signalling pathway is an interesting, potentially new treatment target for schizophrenia; however, the effects of L-lysine need further evaluation to decide the amino acid's potentially beneficial effects on symptom severity in schizophrenia.

Panic disorder and the Defence Mechanism Test.

The aim was to study defence categories according to the modified version of the Defence Mechanism Test (DMTm) and to see if there was a relationship between DMTm and severity of illness. The material consists of 23 patients with panic disorder according to DSM-III-R who participated in a long-term follow-up of two clinical trials. The most common defence categories were repression, denial, disavowal or denial of the threat relation or of the identity of the peripheral person. The patients with denial or polymorphous identification had more severe symptoms and the latter group also were more handicapped by their symptoms. Denial and disavowal or denial of the threat relation may be defence categories, which are not so effective in preventing the individual from experiencing anxiety. Polymorphous identification, although not so common, does not seem to be an appropriate defence among patients with panic disorder.