[Enhancement of eprosartan mesylate dissolution from immediate release tablets in vitro]

Eprosartan mesylate is the latest angiotensin II receptor antagonist approved by FDA. It is used for the treatment of hypertension. It has a low oral bioavailabilty not more than 13%. This study aims to enhance eprosartan mesylate release from immediate release oral tablet by adding solubility enhancers to the formula of the marketed tablet, then comparing dissolution profiles. The formula of the studied tablet was determined by preparing a formula similar to that of the marketed tablet in its physical properties and dissolution profiles. Eprosartan mesylate release from the prepared tablet and the marketed tabled was studied in different dissolution media: HCI acidic medium pH 1.2, phosphate buffer pH 6.8, and phosphate buffer pH 7.5. Results were compared. Spectrophotometer was used to titrate the amount of active ingredient release in the dissolution medium. Titration method by spectrophotometry was validated. Effect of addition of solubility enhancers in various percentages to the formula on eprosartan mesylate release was studied. Tween 80, gypsophila saponin, L-arginin, citric acid, and sodium bicarbonate were used. Statistical study was performed using T-Test and one-way ANOVA Test to compare means of samples at a confidence level of 5%. Consequent Dunnett's Test was used to compare with control sample. The highest release of eprosartan mesylate from the prepared tablet was noted successively in the phosphate buffer pH 7.5, HCI acidic medium pH 1.2, and phosphate buffer pH 6.8. One-way ANOVA Test did not show any statistically significant difference [p>0.05]. Using 6% of Tween 80, 6% of gypsophila saponinin, or L-arginin in a molar ratio 1:3 resulted in minor improvement in dissolution rate 0.05]. Addition of studied solubility enhancers to eprosartan mesylate tablet did not result in statistically significant imrovement of drug release

[Development of different formulae of sustained release metoclopramide suppositories and studying their in -vitro drug release]

Sustained release suppositories are new preparations, which may relief the patient form applying suppositories many times per a day. Metoclopramide hydrochloride is one of the commonly used medicaments, which are good candidates to be formulated as controlled release suppository, as it has short half life. The suppositories were manufactured using fusion method. The drug release profiles from these suppositories were monitored using dissolution tester. It was found that suppositories formulated form the mixture PEG / Ethyl cellulose [65:35 w:w] released Metoclopramide hydrochloride slowly, as its release time lasted for a period of time of 26 hours. Moreover, the mechanical properties of these suppositories were acceptable

Improving paracetamol absorption [oral tablets] by using metoclopramide [single dose]

The aim of this study is to investigate the possibility of improving the rate and extent paracetamol absorption [single oral dose] by increasing rate of gastric emptying by using metoclopramide. So [This makes] paracetamol moves more quickly to the duodenum, which is the preferable site of paracetamol absorption. The study was carried out in twelve healthy male volunteers [Crossover Study]. They were given single oral dose [500 mg paracetamol and 10 mg metoclopramide]. Paracetamol serum concentrations were analyzed by HPLC. Pharmacokinetic parameters were determined by using modified Excel program. The determined parameters were C[max], T[max], AUC, relative F, T[1/2], K, Ka, T[1/2a] and MRT. The results showed improvement in extent of paracetamol absorption when it was given with metoclopramide [F=132 +/- 8%]. They showed also improvement in its absorption rate, which was reflected in decreasing T[max] from 1.333 +/- 0.246 hour to 0.75 hour. Increasing C[max] from 6.458 +/- 1.186 micro g/ml to 12.042 +/- 1.137 micro g/ml, increasing Ka from 1.250 +/- 0.254 to 3.133 +/- 0.250 and decreasing T[1/2a] from 0.581 +/- 0.115 to 0.220 +/- 0.018 hour, which lead to reduction in MRT from 4.467 +/- 0.525 to 3.306 +/- 0.593

[ comparison study between the release of mebeverin hydrochloride from tablets using hydrophilic and insoluble polymers]

Polymers play an important role in the drug release from solid dosage forms, and this importance varies as the kind of polymer and its percentage in the formulation. In this research we reveal the role of hydrophilic polymers or insoluble polymers in the release of mebeverine hydrochloride from sustained release tablets. HPMC15000 had a great effect in controlling the release of mebeverine hydrochloride from tablet after it had been used at rate of 15% in the inner phase, where the release rate of mebeverine hydrochloride reached 70% during 12 hours, and 86% after 24 hours, and when increasing the dose of mebeverine hydrochloride from 200 mg per tablet to 300 mg, it was necessary to increase the rate of HPMC15000 up to 17,5% and the average release was 62% during 12 hours and 86% after 24 hours. But when using neutral polymers of acrylic acid derivatives [Eudragit RL and RSI there were noticed differences in the release rate of mebeverine hydrochloride from the prepared tablets, and that was according to the type of Eudragit used and the rate of hydrophilic groups in it, Eudragit RL caused a total release of mebeverine hydrochloride from tablet after only 8 hours, and a combination of Eudragit RS and RL [3/1] released 90% of mebeverine hydrochloride during 24 hours, while Eudragit RS alone released 80% of this drug

Oral administration of calcium pectinate beads: study of resistance of digestive system at mouse

The controlled pharmaceutical forms, which include pharmaceutical vectors, have not been restricted to vascular, external or respiratory use, but they became useful for digestive system for the treatment of many diseases [1, 4, 15]. That due is to the great advantages of this via system. In this research, we studied the fate of pectin beads after their oral administration to a mouse. Design and Various forms of pectin were used to prepare beads in the presence of calcium ions to obtain egg- box model [2, 20]. This technique has enabled to get beads, which can carry the used active substances into the colon level, after they were coated with a protective material against gastrointestinal effects. 1- Pectin beads with dimensions 900- 1200 microm, were prepared using 6% of calcium ions [w/v]. They had a different swelling time and a good stability [80- 90%] in the gastrointestinal medium. Also they had an ability to release their contained active substance after three hours of their oral administration into studied mouse. 2- Time of active substance release from pectin beads was controlled into five different areas of digestive system of mouse. Also the fate of pectin beads was studied