Publications by authors named "C M Shammi"
Objective: In the treatment of schizophrenia, all currently available oral antipsychotics are administered at least once daily, with strict adherence strongly encouraged to minimize risk of relapse. Based on a better understanding of the brain kinetics of antipsychotics, we have proposed a variation of this approach, "extended" dosing, which allows for intermittent but regular dosing.
Method: We carried out a randomized, double-blind, placebo-controlled trial evaluating 35 individuals with DSM-IV-defined schizophrenia who had been stabilized on antipsychotic therapy.
Objective: To determine the prevalence rates of hepatitis C in patients with schizophrenia and schizoaffective disorder being treated with clozapine.
Methods: Clozapine-treated outpatients and inpatients were recruited from the Centre for Addiction and Mental Health Schizophrenia Program in Toronto, Canada. All subjects had liver function tests, and positive HCV status was defined as a positive qualitative HCV RNA assay.
Objective: Clozapine-induced hypersalivation (CIH) occurs in up to 57% of treated patients and can be the source of considerable subjective distress. Previous open-label studies suggest that sublingual ipratropium bromide may be effective in treating CIH.
Method: We conducted a randomized, double-blind, placebo-controlled crossover trial to evaluate the efficacy of ipratropium in 20 individuals with CIH between September 2006 and August 2007.
Context: Most antipsychotics are thought to have an effect on D(2) and D(3) receptors. The development of carbon 11-labeled (+)-4-propyl-9-hydroxynaphthoxazine ([(11)C]-(+)-PHNO), the first agonist radioligand with higher affinity for D(3) than D(2) receptors, allows one to differentiate the effects of antipsychotics on high-affinity vs low-affinity sites of the D(2) receptor and on D(3) vs D(2) receptor subtypes.
Objectives: To examine the effects of antipsychotics (clozapine, risperidone, or olanzapine) on the high- vs high- + low-affinity sites of the D(2) and D(3) receptors by comparing the [(11)C]-(+)-PHNO and [(11)C]raclopride binding in the D(3) receptor-rich (globus pallidus and ventral striatum) and D(2) receptor-rich (caudate and putamen) regions.
Article Synopsis
- Long-acting risperidone, given intramuscularly once a month, was studied to understand its effect on D(2) dopamine receptor binding in patients with schizophrenia.
- Seven patients received monthly injections and underwent PET scans to measure D(2) binding shortly before their next dose.
- Results showed that even with variable D(2) receptor occupancy levels, some patients maintained stability without relapse, suggesting that high D(2) occupancy might not be essential for ongoing treatment effectiveness.