Formulation and evaluation of buccoadhesive quetiapine fumarate tablets

O objetivo do presente estudo foi desenvolver e avaliar os comprimidos bucoadesivos de fumarato de quetiapina (FQ), que é extensivamente metabolizada no fígado. Os comprimidos bucoadesivos de FQ foram preparados utilizando-se HPMC K4M, HPMC K15M e a combinação de carbopol e HPC como polímeros mucoadesivos pelo método de compressão direta. O desoxicolato de sódio foi adicionado à formulação para melhorar a permeação do fármaco. As formulações foram testadas quanto à força de bioadesão, tempo de residência ex vivo, tempo de inchamento, dissolução in vitro e permeação ex vivo. A formulação otimizada (F3) mostrou 92% de liberação in vivo em 8 h e 67% de permeação do fármaco através da mucosa bucal de porco e seguiu o mecanismo fickiano de liberação com cinética de ordem zero. Os estudos de FTIR da formulação otimizada não mostraram evidência da interação entre o fármaco e os polímeros. O comportamento mucoadesivo in vivo da formulação otimizada foi efetuado e avaliaram-se os parâmetros subjetivos.The aim of present study was to develop and evaluate buccoadhesive Quetiapine Fumarate (QF) tablets, which is extensively metabolised by liver. Buccoadhesive tablets of QF were prepared using HPMC K4M, HPMC K15M and combination of carbopol and HPC as mucoadhesive polymers by direct compression method. Sodium deoxycholate was added to formulation to improve the permeation of drug. The formulations were tested for bioadhesion strength, ex vivo residence time, swelling time and in vitro dissolution studies and ex vivo permeation studies. Optimized formulation (F3) showed 92% in vitro release in 8 h and 67% permeation of drug through porcine buccal mucosa and followed fickian release mechanism with zero order kinetics. FTIR studies of optimized formulation showed no evidence of interaction between the drug and polymers. In vivo mucoadhesive behaviour of optimized formulation was performed and subjective parameters were evaluated

Fast disintegrating tablets of flurbiprofen: formulation and characterization

The purpose of development oral fast disintegrating drug delivery is not only to give fast relief but also to overcome difficulty in swallowing tablets and capsules, resulting in non-compliance and ineffective therapy. The aim of present study is to formulate fast disintegrating of flurbiprofen by using superdisintegrants. Flurbiprofen fast disintegrating tablets were prepared by using direct compression method and were characterized for both pre-compression parameters and post-compression parameters to comply with pharmacopoeial limits. From the in vitro drug release studies the optimized formulation showed almost complete drug release (above 99 %) within 15 min. DSC and FTIR studies were carried out to understand the drug-polymer compatibility and revealed that there was no possible interaction between them. Thus developed fast disintegrating tablets may be suitable to give rapid drug delivery and rapid onset of action.Colegio de Farmacéuticos de la Provincia de Buenos Aire

In vitro transcutaneous permeation of acyclovir sodium from HPMC gels: role of chemical permeation enhancers

The main objective of the present study is to improve the permeation of acyclovir sodium (ACV) across stratum corneum (SC) from HPMC gel formulations. We have also investigated the role of chemical permeation enhancers like dimethyl sulfoxide, ethanol, limonene and sodium taurodeoxycholate on the transcutaneous permeation of ACV from HPMC gels. The optimized formulations were characterized and subjected to in vitro permeation study using excised rat abdominal skin. The histological examination of the skin was studied to understand the mechanisms involved in the permeation of ACV across skin. The cumulative amount of ACV permeated and the increase in permeation parameters (Jss, Kp and ER) were significantly higher for gel formulations compared to marketed formulation. A 2 to 4 fold increase in enhancement ratio clearly indicates the potential of formulating ACV into a gel.Colegio de Farmacéuticos de la Provincia de Buenos Aire

Venlafaxine hydrochloride transdermal patches: effect of hydrophilic and hydrophobic matrix on in vitro characteristics

Transdermal drug delivery systems of venlafaxine hydrochloride were prepared by using combination of hydrophilic (HPMC E15) and hydrophobic (ERS100 and ERL 100) polymers in 1:5, 2:4, 3:3, 4:2, 5:1 ratios by solvent casting technique with 15 % v/w propylene glycol as plasticizer. The drug permeation studies revealed that drug permeation increased proportionally with increasing HPMC ratio where ERS 100 as hydrophobic polymer but in case of ERL 100 as hydrophobic polymer proportional increase was not obtained this may be due to increased diffusion path length. The drug permeation kinetics followed zero order profile with diffusion mechanism. The average steady state flux obtained with HPMC: ERL 100 (3:3) was 193.2 μg/cm2 /h and the same was increased to 257 μg/cm2 /h with the incorporation of 5 % v/w of dimethyl sulfoxide as permeation enhancer that was 3 fold of target flux (86 μg/cm2 /h). The FTIR studies showed drug-polymer compatibility.Colegio de Farmacéuticos de la Provincia de Buenos Aire

Pulmonary Vein Isolation for Vagotonic, Adrenergic, and Random Episodes of Paroxysmal Atrial Fibrillation

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/75410/1/j.1540-8167.2004.03432.x.pd

Formulation and pharmacodynamic evaluation of meloxicam liquisolid compacts

The purpose of this study was to improve the meloxicam dissolution rate through its formulation into liquisolid compacts and then to evaluate the in vitro and in vivo performance of the prepared liquisolid compacts. Dissolution efficiency, mean dissolution time and relative dissolution rate of liquisolid compacts were calculated and compared to marketed formulation. The degree of interaction between the ME and excipients was studied by differential scanning calorimetry and X-ray diffraction were used and results revealed that, there was a loss of meloxicam crystallanity upon liquisolid formulation and almost molecularly dispersed state, which contributed to the enhanced drug dissolution properties. The optimized liquisolid compact showed higher dissolution rates and dissolution efficiency compared to commercial product. The analgesic and anti inflammatory response of optimized liquisolid compact in Swiss albino mice and Wistar rats was found to be superior compared to the marketed formulation.Colegio de Farmacéuticos de la Provincia de Buenos Aire

Prevalence of Asymptomatic Recurrences of Atrial Fibrillation After Successful Radiofrequency Catheter Ablation

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/72183/1/j.1540-8167.2004.04055.x.pd

Lessons to be learnt from Leishmania studies

Leishmaniasis is a disease caused by infection with the protozoan parasite Leishmania, which is responsible for three main types of disease: cutaneous leishmaniasis, visceral leishmaniasis and mucocutaneous leishmaniasis based to the site of infection for the particular species. This presents a major challenge to successful drug treatment, as a drug must not only reach antileishmanial concentrations in infected macrophages, the parasites' host cell, but also reach infected cells in locations specific to the type of disease. In this paper we discuss how studies using Leishmania have contributed to our knowledge on how drug delivery systems can be used to improve drug efficacy and delivery