ABSTRACT
OBJECTIVE: This study was undertaken to compare the pharmacokinetic profiles of paroxetine oral solution and paroxetine tablets in healthy volunteers under fasting conditions. METHODS: In this randomized, open-label, single-dose, 2-way cross over, laboratory-blind bioequivalence study healthy volunteers alternately received one 20 mg dose paroxetine as an oral solution (20 mg/20 drops) and one 20 mg dose paroxetine as a tablet. Doses were separated by a 23-day interval. RESULTS: A total of 48 subjects enrolled in the study; there were 26 males and 22 females with a median age of 25.5 years and a median weight of 73.6 kg. Both formulations were well tolerated, with no serious adverse events reported. Two subjects discontinued the study. Paroxetine was rapidly absorbed, the rate and extent of absorption of the two formulations were similar, and no statistically significant differences in half-life were observed between formulations. CONCLUSION: The oral solution and tablet formulations of paroxetine were bioequivalent and therefore may be safely interchanged. The oral solution may be a useful tool to ease administration and for tapering off paroxetine treatment.
Subject(s)
Paroxetine/pharmacokinetics , Selective Serotonin Reuptake Inhibitors/pharmacokinetics , Administration, Oral , Adolescent , Adult , Area Under Curve , Cross-Over Studies , Diarrhea/chemically induced , Dizziness/chemically induced , Dose-Response Relationship, Drug , Double-Blind Method , Drug Administration Schedule , Female , Half-Life , Headache/chemically induced , Humans , Male , Mesylates/chemistry , Middle Aged , Nausea/chemically induced , Paroxetine/administration & dosage , Paroxetine/adverse effects , Paroxetine/blood , Pharmaceutical Solutions/administration & dosage , Pharmaceutical Solutions/adverse effects , Pharmaceutical Solutions/pharmacokinetics , Selective Serotonin Reuptake Inhibitors/administration & dosage , Selective Serotonin Reuptake Inhibitors/adverse effects , Tablets , Therapeutic Equivalency , Vomiting/chemically inducedABSTRACT
UNLABELLED: Risperidone is an atypical anti-psychotic, available in various formulations. OBJECTIVE: The objective of the study was to compare the bioavailability of a generic oral solution of risperidone (Test formulation) and Risperdal tablets (Reference formulation). Both formulations contained 1 mg risperidone per dosing unit. METHODS: The study was carried out in 32 healthy volunteers under fasting conditions. Risperidone and 9-hydroxyrisperidone concentrations in plasma were determined using HPLC/MS/MS. RESULTS: The results show that the 90% confidence intervals for the geometric mean ratios of the solution and the tablet formulations were not within the acceptance range of 80 125% for risperidone, whereas the confidence intervals for 9-hydroxyrisperidone were within the acceptance range of 80 - 125%. CONCLUSION: Bioequivalence between the generic 1 mg/ml risperidone solution and the originator tablet formulation was not proven in this study.
