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Objective : To study prevalence and clinical features of myasthenia gravis (MG) and myasthenia gravis with hyperthyroidism (MGHT) Design : Case review study Setting : Srinagarind hospital, Faculty of Medicine, Khon Kaen University Patienes : One hundred and four patients who were diagnosed as MG and MGHT in Department of Internal Medicine service between Januay 1891 and May 1992. Measurement : Prevalence of MGHT, history of fatigability, fluctuation, staging, symptoms and signs, prostigmine test and treatment by thymectomy in MG and MGHT by percentage and Z – test ( P = 0.05) Results : One hundred and four records were available for review, there were 85 cases of MG and 19 cases of MGHT that made the prevalence of MGHT of 18.3%. Regarding the staging of disease, in MG group of patients only 8.2% were in stage I compared to 31.6% in MGHT group( P = 0.003). Ninty four percent of MGHT patients seeked medical attention within 1 year after having MG, but there were only 77.2% in MG patients ( P = 0.048). Concerning thymectomy, in the patients who had stage IIA and above, 58 / 78 (74.4%) were thymectized in MG group. There were only 5/13 (38.5%) in MGHT group went for thymectomy (p = 0.048). The other clinlical features were comparable. The pathological findings of 50 patients in MG group were thymic hyperplasia 34 cases (68%) , htymoma 2 cases, malignant thymoma 1 case atrophic change 5 cases and normal 8 cases. In MGHT goup were thymic hyperplasia 4 cases and involuted 1 case. Concludions : The prevalence of myasthenia gravis with hyperthyroidism in our study is 18.3%, which probably is the highest among all series. There were differences in some clinical features between MG and MGHT. MGHT patients were in stage 1 more frequent, seeked medical aedical altention earlier and MGHT patients went for thymectomy less frequent.
ABSTRACT
Background: Clozapine is an atypical antipsychotic drug that has been used world wide for the treatment of schizophrenic patients. Several generic formulations of this drug are now available.\ In order to assure about the efficacy and safety of the generic formulation, it is necessary to compare the bioavailability between the generic and the reference formulations after administration to the patients.Purpose: To compare the bioavailabilty of two clozapine formulations, Clozapin (Pharmasant Laboratories Co., Ltd., Thailand) and Clozaril (Novartis Pharmaceuticals, UK) when administered to schizophrenic patients in the dose of 100 mg every 12 hr until the drug reach steady state.Study design : Multiple dose steady state, randomized crossover study under non-fasting condition.\ The study was approved by the Ethics Review Board of the Khon Kaen University and the Food and Drug Administration, Ministry of Public Health.Subject : 18 Male Thai schizophrenic patients Methods: The subjects received 100 mg of either the Clozapin or Clozaril\ per oral bid for 7 days. At day 7 of each study phase, the drug levels were reached the steady state/\ Two hour after meal, the drug was administered and\ blood samples were collected at 0, 0.5, 1, 1.5, 2, 2.5, 3, 4, 6, 8, 10 and 12 hr. Plasma was separated and stored at \–80oC until assay. The plasma concentration of clozapine was determined by high performance liquid chromatography. Pharmacokinetic parameters were calculated from the plasma-concentration time profiles. The bioequivalence between the two formulations was assessed from the peak plasma concentrations (Cmax) and area under the concentration-time curve (AUC0-12 ) ratios.\ Results: All subjects well tolerated both clozapine formulations. No serious adverse effects were reported. The Tmax, terminal half-life and the total plasma clearance of clozapine observed in the present study were comparable to those observed in other previous reports. All of the evaluated pharmacokinetic parameters between the Test and Reference formulations were of comparable. The 90% confident interval for the ratio of means for the LnCmax (0.9453-1.1182) and LnAUC0-12 (0.9734-1.0889) are within the guideline range of bioequivalence (0.80 to 1.25). Conclusion: The result demonstrated that the Test formulation, Clozapin was bioequivalent to the Reference formulation, Clozaril when orally administered in multiple \–dose to schizophrenic patients.
ABSTRACT
Background: Sildenafil is a popular drug used for improving penile erectile function that has been commercially available through several manufacturers and distributors in Thailand. Therefore, it is necessary to study bioequivalence of the drugs obtained from the original manufacture and from a local manufacturer to ascertain that they can be medicated interchangeably.Objective: To determine whether two sildenafil preparations: Test (Erec®, Unison Laboratories, Co., Ltd., Thailand) and reference, (Viagra®, Pfizer Pty Limited., Australia) are bioequivalent.Design: Single oral dose and double-blind randomized two-way crossover.Population and samples: Fifteen healthy Thai male volunteers.Setting: Department of pharmacology, and Srinagarind Hospital, Faculty of Medicine, Khon Kaen University.Methods: The subjects received either 100 mg of the reference or test formulation. Blood samples were collected from catheter at several time points after sildenafil administration up to 12 hours. The bioequivalence between the two formulations was assessed by comparison of the peak plasma concentrations (Cmax) and area under the curve of time, from 0 to the last measurable concentration (AUC0-t last).Results: All subjects were well tolerated and presented no serious side effect. Statistical analysis revealed that the 90% confident intervals (CI) for the ratios between test and reference drugs of the log transformed the Cmax (0.8377-1.1985) and AUC0-t last (0.8610-1.1590), are within the Food and Drug Administration Guideline range of bioequivalence (0.80 to 1.25).Conclusions: It can be concluded that the 100 mg formulation of Test (Erec®) is bioequivalent to the Reference.Keywords: sildenafil, bioequivalence