Treatment-resistant schizophrenia - A RCT on the effectiveness of repeated-dose sodium nitroprusside.

OBJECTIVES: Sodium nitroprusside (SNP) has shown efficacy in schizophrenia in early stages of the disease in a previous study, but in more recent studies it has not shown efficacy in patients with longer disease duration. In present study, we evaluated the efficacy of repeated-dose SNP in treatment-resistant schizophrenia. METHODS: This was a double-blind, randomized, placebo-controlled trial. Twenty DSM-IV schizophrenia subjects, aged 18-60 years, with a history of nonresponse to ≥2 trials of antipsychotics of adequate dose and duration (≥6 weeks) were enrolled. Participants received SNP or placebo 4-hour infusions at 0.5 µg/kg/min. A total of 4 infusions and 4 follow-up evaluations, with an interval of 2 weeks, were performed. Severity of symptoms were assessed by using Positive and Negative Syndrome Scale (PANSS), Brief Psychiatric Rating Scale (BPRS-18) and Clinical Global Impression (CGI) scales. RESULTS: SNP and placebo groups did not differ at baseline or in change from baseline for PANSS-total (F = 0.525; p = 0.841), PANSS-positive (F = 0.32; p = 0.958), PANSS-negative (F = 1.05; p = 0.483), BPRS (F = 0.615; p = 0.734), or CGI-S (F = 1.11; p = 0.416) scores. SNP was well tolerated and showed a good safety profile. CONCLUSION: Although preliminary, the present findings suggest that SNP is not efficacious in TRS, reinforcing previous studies that have not demonstrated symptom improvement in chronic schizophrenia subjects. At this time, it is conceivable to speculate that efficacy of SNP might be restricted to early stages of disease.

Insights into the Effects of Crack Abuse on the Human Metabolome Using a NMR Approach.

Approximately 255 million people consume illicit drugs every year, among which 18 million use cocaine. A portion of this drug is represented by crack, but it is difficult to estimate the number of users since most are marginalized. However, there are no recognized efficacious pharmacotherapies for crack-cocaine dependence. Inflammation and infection in cocaine users may be due to behavior adopted in conjunction with drug-related changes in the brain. To understand the metabolic changes associated with the drug abuse disorder and identify biomarkers, we performed a 1H NMR-based metabonomic analysis of 44 crack users' and 44 healthy volunteers' blood serum. The LDA model achieved 98% of accuracy. From the water suppressed 1H NMR spectra analyses, it was observed that the relative concentration of lactate was higher in the crack group, while long chain fatty acid acylated carnitines were decreased, which was associated with their nutritional behavior. Analyses of the aromatic region of CPMG 1H NMR spectra demonstrated histidine and tyrosine levels increased in the blood serum of crack users. The reduction of carnitine and acylcarnitines and the accumulation of histidine in the serum of the crack users suggest that histamine biosynthesis is compromised. The tyrosine level points to altered dopamine concentration.