In-vitro and in-vivo evaluation of sustained-release suppositories containing theophylline microspheres

The sustained release microspheres of theophylline were formulated using non-solvent addition technique. The in-vitro dissolution of the drug from the fabricated microspheres that having size ranges of 300-600, 600-800 and 800-1000 [micro]m was tested The release of theophylline was extended over 8 hrs and it was found that the drug release decreased nonsignificantly as the particle size increased [p>/=0.05]. incorporating theophylline-containing microspheres into suppository formulation using polyethylene glycol base resulted in a slight increase in dissolution rate, but still in a sustained release pattern over 8 hrs. In-vivo study of the prepared suppositories on beagle dogs revealed that the peak of theophylline serum concentration C[max] [mean +/- S.D] was 11.1+0.3 [micro]g/mL. It was also found that AUC [0-24hrs] value averaged 154.7 +/- 20.3 [micro]g-h/ml. The median peak time [T[max]] was 3.0 hrs and MRT was 13 hrs indicating a sustained effect

Ketorolac enteric matrix pellets produced by extrusion / spheronization

Ketorolac is a non-steroidal anti-inflammatory drug used in the treatment of pain. However, it has side effects including gastrointestinal [GI] irritation when administered orally. The oral administration of conventional oral dosage forms of ketorolac can cause serious gastrointestinal side effects and gastric irritation due to dose dumping. The objective of this study was to prepare enteric matrix pellets of the drug that lower the risk of side effects by the formulation of Eudragit / microcrystalline cellulose [Avicel PH 101] pellets using extrusion / spheronization technique. Moreover, mixer torque rheometer was used to quantitatively determine the suitable moisture content in the pastes before the extrusion process. The produced pellets were characterized for their ketorolac content, particle size, shape and dissolution profile. Studies on the effect of additives [Avicel and PVP] on Eudragit rheological properties revealed that the magnitude of torque lowered as the Avicel ratio increased, a fact that reflected on the roundness of the produced pellets. The release of the drug is controlled by the Eudragit / Avicel ratio. In some formulations, in acidic medium, the release of the drug was less than 10% after 2 hrs, while it is completely released within 60-120 mm after changing dissolution medium to phosphate buffer [pH 6.8]. In conclusion, the manufactured pellets delayed drug release rates as well as it successfully passed the USP requirements for enteric delayed release articles, which might be beneficial in lowering the risk of side effects as an advantage of the pellets as drug delivery system without the need for tedious enteric coating process

Proniosomes as a drug carrier for transdermal delivery of meloxicam

The current investigation aims to evaluate the potential of proniosomes as a carrier for transdermal delivery of a potent non-steroidal anti-inflammatory, meloxicam. Meloxicamloaded proniosomes were prepared and characterized for entrapment efficiency, surface morphology and in-vitro permeation across excised rat skin from various proniosome gel formulations using Franz diffusion cells. Various non-ionic surfactants were used to achieve optimum encapsulation efficiency. Niosomes formed from using Spans and Tweens exhibited high encapsulation efficiency. The prepared proniosomes significantly improved drug permeation and reduced the lag time [p<0.05]. Proniosomes prepared with Span 60 provided a higher meloxicam flux across the rat skin than did those prepared with Tween 80. Testing of the anti-inflammatory effect of meloxicam proniosomal gel showed better pharmacological activity when compared with the standard meloxicam gel. The results suggest that proniosomes can act as promising carriers offer an alternative approach for transdermal delivery of meloxicam

Preparation and comparative evaluation of sustained release metoclopramide hydrochloride matrix tablets

Metoclopramide hydrochloride [MCP] is commonly used for the management of gastrointestinal disorders. Frequent administration and the undesired side effects [extra pyramidal symptoms] of the drug on the central nervous system due to the fluctuations of its plasma concentrations may lead to patient incompliance, and hence, improper therapy. Therefore, the present work will be devoted to formulate the drug in sustained release formulations. MCP was incorporated in 12 formulae containing different polymers and/or different polymer ratios. These polymers were hydroxypropylmethyl cellulose [HPMC], carboxymethylcellulose [CMC] and ethyl cellulose [EC]. Sodium starch glycolate [SSG] was added to some formulae in different amounts in order to soften and/or disintegrate the tablets. The physical properties were found to be satisfactory for all the formulae. The dissolution profiles of the tablets were constructed using the change-over method. The drug release involved a combination of both diffusion and polymer-chain relaxation mechanisms. The time required to release 50% of MCP ranged from 1.2 to more than 8 hours. Direct compression and dry granulation techniques produced sufficient sustaining of the drug release. However, the pellets made by wet granulation released MCP in about 2 hrs, i.e., Pelletization spheronization technique was not effective in sustaining the drug

Effects of sphere size, polymer to drug ratio and plasticizer concentration on the release of theophylline from ethylcellulose microspheres

Theophylline sustained release microspheres were prepared by applying the non-solvent addition method. The in-vitro release of the drug from the prepared microspheres of different size ranges [