PubMed Health⌕ Search

SEARCH · PubMed Health

Results for “Tablets”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 1,189 records · Page 66Linked to original sources

Preparation and in vitro evaluation of sustained release tablet formulations of diclofenac sodium.

The effects of formulation variables on the release profile of diclofenac sodium (DS) from hydroxypropylmethyl cellulose (HPMC) and chitosan matrix tablets were studied. DS tablets were prepared by wet granulation and direct compression methods and different ratios of HPMC and chitosan were used. Physical properties of the prepared tablets and targeted commercial sustained release (SR) tablet and the drug release were studied in tablets that were placed in 0.1 M HCl for 1 h and phosphate buffer solution was added to reach pH value of 7.5. In vitro studies showed that 20% HPMC contained SR formulation with direct (dry) compression method is the optimum formulation due to its better targeting profile in terms of release. This formulation also exhibited the best-fitted formulation into the zero order kinetics. The precision and accuracy of the analytical method were also checked. The repeatability and reproducibility of the method were also determined.

Chemistry, Pharmaceutical↗

Gamma scintigraphic evaluation of film-coated tablets intended for colonic or biphasic release.

The gastrointestinal transit and in vivo drug release behaviour of a film-coated tablet formulation was investigated in five healthy human subjects using the technique of gamma scintigraphy. The film coating system consisted of a mixture of pectin, chitosan and HPMC in a ratio of 6:1:0.37 applied to 750 mg cores at a coat weight gain of 9%. The estimated mean values of the gastric emptying time (62+/-17 min), small intestinal transit time (219+/-53 min), ileocaecal junction lag time (79+/-30 min) and the colon arrival time (345+/-33 min), were similar to published values for the transit of similar sized tablets in humans. The amount of radioactive tracer released from the labelled tablets was minimal when the tablets were in the stomach and the small intestine. There was increased release of radioactivity when the tablets were in the colon due to increased degradation of the film coatings by pectinolytic enzymes resident in the colon. The pectin/chitosan/HPMC film coating system thus acts as a colonic delivery system.

Acetaminophen↗

Design of a dissolution system for the evaluation of the release rate characteristics of artemether and dihydroartemisinin from tablets.

As none of the pharmacopoeial dissolution methods are suitable to evaluate the release rate of artemether and dihydroartemisinin from tablets, a 'two-phase partition-dissolution' method, based on the one of [J. Pharm. Sci. 85 (1996) 1060] was developed. It consists of an organic solvent in the upper part and the aqueous phase, in which the dissolution test was executed. The main requirements for the selection of the solvent are: the density should be lower than 1; the analyte should dissolve in the organic part as much as required for 'sink' conditions; if possible, the cut off should be near 200 nm, which allows direct HPLC measurement at 215 nm. The most suitable solvent for artemether is isooctane in a ratio of 100/150 ml aqueous phase. Samples could be analysed without further treatment. For dihydroartemisinin, chlorobutane was selected in a ratio 150/150 ml water. In the latter method, the solvent disturbed in the HPLC analysis and therefore samples were evaporated and then reconstituted in methanol. Repeatability of the test was satisfactory and discrimination ability tests on Artenam tablet batches and self-made dihydroartemisinin tablets, respectively, showed good results, confirmed via calculation of the similarity factor f2 (value <50). Dissolution determination of Cotecxin tablets was proven not to be conform as immediate-release tablet.

Artemether↗

A dosage design of mitomycin C tablets containing finely powdered green tea.

We previously reported a method of preparing finely powdered green tea (PT), powder characteristics and release profiles of green tea components from PT. In this study, we performed formulation studies of PT tablets containing mitomycin C (MMC), expecting its combined antitumor effects with mitomycin C and green tea components. The hardness of PT tablets was low (22-50 N) and the disintegration time was about 180 min regardless of hardness or tabletting pressure (15-200 MPa). Perfiller-101 improved tablet characteristics practically into 90 N of hardness and 18.5 min of disintegration time. Release rates of MMC, caffeine and EGCG from the tablets were similar, and depended on the disintegration time. PT and epigallocatechin gallate (EGCG) increased significantly in MMC uptake in Ehrlich ascites carcinoma cells as compared with the control dose-dependently in vitro.

Animals↗

The preparation of orally disintegrating tablets using a hydrophilic waxy binder.

The demand for rapidly disintegrating tablets (RDT) has been growing during the last decade especially for elderly and children who have swallowing difficulties. The problem of certain RDT is their low physical resistance and high friability. This work describes a new approach to prepare RDT with sufficient mechanical integrity, involving the use of a hydrophilic waxy binder (Superpolystate, PEG-6-stearate). Superpolystate is a waxy material with a melting point of 33-37 degrees C and an HLB value of 9. So it will not only act as a binder and increase the physical resistance of tablets but will also help the disintegration of the tablets as it melts in the mouth and solublises rapidly leaving no residues. The incorporation of Superpolystate in the formulation of RDT was realised by means of two different granulation methods: wet granulation by using an emulsion of this waxy binder as granulating liquid and melt granulation where the molten form of the binder was used. Granule size distributions of both wet and melt granules of crystallised Paracetamol and D-mannitol were compared using laser light diffractometer. Scanning electron microscopy (SEM) was used to examine their morphological characteristics. The potential of the intragranular addition of croscarmellose sodium as a disintegrating agent was also evaluated. The subsequent step encompassed the preparation and the evaluation of the tablets, including the effect of the extragranular introduction of croscarmellose sodium. An improvement in tablet hardness and friability was observed with both granulation methods where we were able to obtain RDT with a disintegration time of 40 +/- 2 s and a hardness of 47.9 +/- 2.5N.

Acetaminophen↗

Stability study of losartan/hydrochlorothiazide tablets.

The purpose of stability testing is to investigate how the quality of a drug product changes with time under the influence of environmental factors, to establish a shelf life for the product and to recommend storage conditions. Stability study of losartan/hydrochlorothiazide tablets is presented in this paper. Losartan (angiotensin II receptor antagonist) and hydrochlorothiazide (diuretic) are successfully used in association in the treatment of hypertension. Stability study of losartan/hydrochlorothiazide tablets consisted of three steps: stress test (forced degradation study), preliminary testing (selection of packaging) and formal stability testing. The results of stress test suggested that losartan/hydrochlorothiazide tablets are sensitive to moisture. It was demonstrated that the developed analytical methods are stability indicating. Additional preliminary testing was performed in order to select appropriate packaging for losartan/hydrochlorothiazide tablets. OPA/Al/PVC//Al blisters were found to provide adequate protection for the product. Based on the first 12 months of the formal stability study, a shelf life of 24 months was proposed. Losartan/hydrochlorothiazide tablets in OPA/Al/PVC//Al blisters are demonstrated to be chemically, physically and microbiologically stable.

Drug Combinations↗

In vivo evaluation of time and site of disintegration of polysaccharide tablet prepared for colon-specific drug delivery.

Compression coating has been found to be useful for colonic drug delivery. The aim of the present investigation was to evaluate a formulation with a considerably reduced coat weight and gum concentration for colonic drug delivery in vivo using gamma scintigraphy. In vitro studies have found this formulation to be useful for delivery of 5-fluorouracil to the colon. Rapidly disintegrating core tablets containing (99m)Tc-DTPA were prepared and compression coating with 150 mg of granules containing a mixture of xanthan (XG), guar gum (GG) and starch. The ratios of the two gums XG:GG in the coat was kept 10:20. In vitro dissolution studies on XG:GG::10:20 tablets containing (99m)Tc-DTPA were carried out in simulated upper GIT conditions and also in presence of colonic contents. Cumulative percent release of technetium in the upper GIT conditions and transit time amounted to 4%. The total amount of technetium released in the 24 h of the dissolution study was 53+/-3.23%. Upon introduction of cecal content into the dissolution medium (4%), the release of technetium from the compression-coated tablet increased to 78.34+/-5.34%. Gamma scintigraphy studies carried out in six healthy human volunteers showed that the tablet remained intact during its transit through the upper GIT. The anatomical site of disintegration was found to be the ascending colon/hepatic flexure and the disintegration of the tablet started between 4 and 6 h post-dose in all the volunteers with a further spread of tracer into the ascending, transverse, descending and sigmoidal colon.

Adult↗

An investigation of the disintegration of tablets in biorelevant media.

The purpose of the study was to examine the disintegration of tablets in media designed to simulate conditions pertaining in the stomach. Although many studies have been performed to determine dissolution rates in these media, little work has been undertaken on the preliminary step in dissolution, namely disintegration. Two tablet formulations were prepared. One disintegrated rapidly (under 25 s in water) and the other more slowly (8 min in water). The disintegration times were measured by the BP 2000 test using discs. For the rapidly disintegrating tablets, disintegration times were similar in all media except for whole milk. This media is used to simulate the fed stomach and disintegration times were over five times longer than in the other media (P < 0.05). A similar effect was seen with the poorly disintegrating tablets in milk, and prolonged times were also observed in some of the other media. For these latter media, there was a good correlation between the penetration rate of the fluid into the tablet and the disintegration time. Penetration rates for milk were also slow which may be a reflection of its relatively high viscosity and low surface tension.

Chemistry, Pharmaceutical↗

Formulation design of a novel fast-disintegrating tablet.

As our society is becoming increasingly aged, the development of an appropriate dosage form for the elderly patients is mostly desirable. A novel fast-disintegrating tablet was investigated in this study as a user-friendly dosage form for the aged. Advantages of this formulation have sufficient hardness and can be manufactured by commonly used equipment. Saccharides can be divided into high- and low-compressibility categories, and an appropriate material for fast-disintegrating tablets was created by taking advantage of this fact. To improve the compressibility of low-compressibility saccharides, particle modification was conducted by coating and granulating a low-compressibility saccharide with a high one to enable the production of a fast-disintegrating tablet. Another discovery was that the high-compressibility saccharide used as a binder solution was present in an amorphous state after the granulation process. The crystal change from amorphous to crystal state intentionally by a conditioning process after compression enabled to increase tablet hardness by strengthening adhesion between particles. The conditioning process made it possible to achieve sufficient hardness while maintaining the fast disintegration time. As a result, this fast-disintegrating tablet that can be manufactured by commonly used equipment, can be used for the dosing of a wide range drugs.

Acetaminophen↗

Evaluation of rapidly disintegrating tablets containing glycine and carboxymethylcellulose.

A rapidly disintegration tablet in the oral cavity was prepared using a glycine as a disintegrant. Effect of disintegrant on the disintegration behavior of the tablet in the oral cavity was evaluated. Wetting time prepared from carboxymethylcellulose (NS-300) having the hardness of 4 kg was 3 s. Tablet containing NS-300 showed fastest disintegration compared to other formulations. These results suggested that NS-300 possessed excellent wetting nature and resulted in the rapid disintegration of tablet. Ethenzamide and ascorbic acid were added to the formulation, and their disintegration behavior were evaluated. Ethenzamide did not affect the disintegration property, however, ascorbic acid prolonged disintegration time. It was suggested that the tablet formulation containing NS-300 and glycine was highly applicable to water-insoluble drug, such as ethenzamide.

Ascorbic Acid↗

In vitro controlled release of sodium ferulate from Compritol 888 ATO-based matrix tablets.

A controlled release matrix formulation for freely water-soluble drug of sodium ferulate (SF) was designed and developed to achieve a 24h release profile. Using Compritol 888 ATO as an inert matrix-forming agent to control the release of SF, formulation granules containing the physical mixtures or solid dispersions were investigated. The matrix tablets for these formulations were prepared by direct compression and their in vitro release tests were carried out. The solid dispersion based tablets were found to be more effective than those compressed from physical mixtures in retarding the release of SF. Drug release from the matrix tablets containing physical mixtures nearly completed within 12h, while that from the solid dispersion formulations lasted for over 24h. Images of the tablet surface and cross-section were characterized by scanning electron microscopy to show the formed pores and channels in the matrices. These might provide the release pathway for the inner embedded drugs. Drug released fast from the matrix tablets with the release-enhancer of lactose. The addition of surfactants was also found to increase the release rate of SF effectively. Moreover, the co-mixing of polyethylene glycol 6000 (PEG 6000) in the waxy matrices played a meaningful role in controlling the drug release for 24h. The drug release from the novel formulation might be attributed to the diffusion-controlled mechanism.

Chemistry, Pharmaceutical↗

In vitro and in vivo evaluation of medicinal carbon granules and tablet on the adsorption of acetaminophen.

Medicinal carbon (MC) granules were prepared by wet granulation using maltitol (MT), and the MC tablet was produced by compression of the granules. The physical properties and the in vitro adsorption capacity for AA of the formulations were examined. Further, the effects of MC alone and the granules on gastrointestinal absorption of AA were examined in rats when they were administered intragastrically at 15 or 45 min after the intragastrical administration of AA. AA was rapidly adsorbed by MC, and the maximum adsorption capacity of MC was 0.329g AA per gram MC. The granules and tablet exhibited adequate strength, and the tablet disintegrated rapidly. The granules and tablet showed similar adsorption profiles, but somewhat lower adsorption capacity than MC alone. MC alone and granules administered at 15 min reduced the AUC(0-infinity) significantly against the control (no treatment); however, the suppression effect on the plasma concentration was lower with the granules than with MC alone. Thus, granules and tablet are useful as a compact dosage form of MC; though the reduced adsorption capacity must be taken into account in order to expect efficacy equivalent to that of MC alone.

Acetaminophen↗

Alginate-magnesium aluminum silicate films: effect of plasticizers on film properties, drug permeation and drug release from coated tablets.

The effect of hydrophilic plasticizers, namely glycerin and polyethylene glycol 400 (PEG400), on physicochemical properties of sodium alginate-magnesium aluminum silicate (SA-MAS) microcomposite films was characterized and application of the films for controlling drug release from tablets was evaluated as well. The plasticizers could possibly interact with SA or MAS by formation of hydrogen bonding, as revealed using FTIR spectroscopy. PXRD studies presented that glycerin or PEG400 could intercalate into the silicate layers of MAS and higher crystallinity of the films with PEG400 was obtained. This led to a different thermal behavior of the films. Glycerin gave more flexibility of the films than PEG400. Incorporation of plasticizers into the films did not affect water uptake in acid medium, but increasing an erosion of the films because of the leaching of the plasticizers. Water vapor permeability of the films decreased with increasing amount of plasticizers in the range of 10-30% (w/w). Diffusion coefficient (D) of acetaminophen (ACT) across the films in acid medium increased with addition of the plasticizers because the leaching of plasticizers could reduce tortuosity of aqueous pore channels of the films. The tablets coated with plasticized films had a quite smooth surface without defect as shown by SEM. The ACT release profiles from the coated tablets showed a zero-order release kinetic with drug diffusion mechanism across in situ insoluble composite films in acid medium, and coating film swelling and erosion mechanism in pH 6.8 phosphate buffer. Moreover, neither the release rate nor the release pattern of the ACT coated tablets was obviously changed. The findings show that glycerin or PEG400 could improve physicochemical properties of the SA-MAS films and the plasticized films could control the drug release from tablets in gastro-intestinal condition.

Acetaminophen↗

Sublingual epinephrine tablets versus intramuscular injection of epinephrine: dose equivalence for potential treatment of anaphylaxis.

BACKGROUND: Epinephrine autoinjectors are underused in the emergency treatment of anaphylaxis in the community, perhaps in part because of fear of needles. OBJECTIVES: To determine the sublingual epinephrine dose from a novel fast-disintegrating tablet required to achieve epinephrine plasma concentrations (EPPCs) similar to those obtained after epinephrine 0.3 mg intramuscular injection. METHODS: In a prospective 5-way crossover study, sublingual tablets containing epinephrine 0, 10, 20, and 40 mg, and epinephrine 0.3 mg intramuscular in the thigh (EpiPen) were compared in a validated rabbit model. Blood samples were collected before dosing and 5, 10, 15, 20, 30, 40, 60, 90, 120, 150, and 180 minutes afterward. EPPCs were measured by using high-performance liquid chromatography-electrochemical detection. Pharmacokinetic parameters were calculated by using WinNonlin. RESULTS: The area under the curve (AUC), maximum concentration (C(max)), and time at which C(max) was achieved (T(max)) did not differ significantly (P > .05) after epinephrine 40 mg (AUC = 1861 +/- 537 ng/mL/min, C(max) = 31.0 +/- 13.1 ng/mL, and T(max) = 9 +/- 2 minutes) and epinephrine 0.3 mg intramuscular (AUC = 2431 +/- 386 ng/mL/min, C(max) = 50.3 +/- 17.1 ng/mL, and T(max) = 21 +/- 5 minutes). The AUC after tablets containing epinephrine 0 mg (AUC = 472 +/- 126 ng/mL/min), epinephrine 10 mg (AUC = 335 +/- 152 ng/mL/min), and epinephrine 20 mg (AUC = 801 +/- 160 ng/mL/min) did not differ significantly from each other, but were significantly lower (P < .05) than the AUC after epinephrine 0.3 mg intramuscularly. CONCLUSION: Sublingual administration of epinephrine 40 mg from this tablet formulation resulted in EPPCs similar to those obtained after epinephrine 0.3 mg intramuscular injection in the thigh. CLINICAL IMPLICATIONS: For treatment of anaphylaxis in the community, self-injectable epinephrine is underused. This novel, fast-disintegrating epinephrine tablet formulation for sublingual administration is a feasible alternative that warrants further development.

Administration, Sublingual↗

Efficacy and safety of sublingual immunotherapy with grass allergen tablets for seasonal allergic rhinoconjunctivitis.

BACKGROUND: Allergen immunotherapy (desensitization) by injection is effective for seasonal allergic rhinitis and has been shown to induce long-term disease remission. The sublingual route also has potential, although definitive evidence from large randomized controlled trials has been lacking. OBJECTIVE: The aim was to confirm the efficacy of a rapidly dissolving grass allergen tablet (GRAZAX, ALK-Abelló, Hørsholm, Denmark) compared with placebo in patients with seasonal rhinoconjunctivitis. METHODS: A longitudinal, double-blind, placebo-controlled, parallel-group study that included 51 centers from 8 countries. Subjects were randomized (1:1) to receive a grass allergen tablet or placebo once daily. A total of 634 subjects with a history of grass pollen-induced rhinoconjunctivitis for at least 2 years and confirmation of IgE sensitivity (positive skin prick test and serum-specific IgE) were included in the study. Subjects commenced treatment at least 16 weeks before the grass pollen season, and treatment was continued throughout the entire season. RESULTS: The primary efficacy analysis showed a reduction of 30% in rhinoconjunctivitis symptom score (P < .0001) and a reduction of 38% in rhinoconjunctivitis medication score (P < .0001) compared with placebo. Side effects mainly comprised mild itching and swelling in the mouth that was in general well tolerated and led to treatment withdrawal in less than 4% of participants. There were no serious local side effects and no severe systemic adverse events. CONCLUSION: Sublingual immunotherapy with grass allergen tablets was effective in grass pollen-induced rhinoconjunctivitis. The tablet was well tolerated with minor local side effects. CLINICAL IMPLICATIONS: The grass allergen tablet represents a safe alternative to injection immunotherapy suitable for home use.

Administration, Sublingual↗

Oral insulin delivery: the potential of thiolated chitosan-insulin tablets on non-diabetic rats.

It was the aim of this study to develop a delivery system providing an improved efficacy of orally administered insulin utilizing a thiolated polymer. 2-Iminothiolane was covalently linked to chitosan. The resulting chitosan-TBA (chitosan-4-thiobutylamidine) conjugate exhibited 453.5+/-64.1 micromol thiol groups per gram polymer. 3.1% of these thiol groups were oxidised. Additionally, the enzyme inhibitors BBI (Bowman-Birk-Inhibitor) and elastatinal were covalently linked to chitosan representing 3.5+/-0.1% and 0.5+/-0.03% of the total weight of the resulting polymer conjugate, respectively. Chitosan-TBA conjugate (5 mg), insulin (2.75 mg), the permeation mediator reduced glutathione (0.75 mg) and the two inhibitor conjugates (in each case 0.75 mg) were compressed to so-called chitosan-TBA-insulin tablets. Control tablets consisted of unmodified chitosan (7.25 mg) and insulin (2.75 mg). Chitosan-TBA-insulin tablets showed a controlled release of insulin over 8 h. In vitro mucoadhesion studies showed that the mucoadhesive/cohesive properties of chitosan were at least 60-fold improved by the immobilisation of thiol groups on the polymer. After oral administration of chitosan-TBA-insulin tablets to non-diabetic conscious rats, the blood glucose level decreased significantly for 24 h corresponding to a pharmacological efficacy of 1.69+/-0.42% (means+/-S.D.; n=6) versus s.c. injection. In contrast, neither control tablets nor insulin given in solution showed a comparable effect. According to these results the combination of chitosan-TBA, chitosan-enzyme-inhibitor conjugates and reduced glutathione seems to represent a promising strategy for the oral application of insulin.

Adhesives↗

Development of implant tablet for a week-long sustained release.

An implant tablet for a week-long sustained release was developed by the direct compression method using poly-DL-lactic acid (PLA) and poly(DL-lactic acid-co-glycolic acid) copolymer (PLGA) as a matrix and phenol red (PR) as a model drug. The in vitro release was affected by formulations, especially by drug content and polymer species. The release rate correlated with the rate of absorption of water. The implant tablet (30 mg) containing 1 mg of PR, prepared using PLGA (MW 10,000; lactic acid/glycolic acid=1:1, mol/mol) by compression at 50 kg/cm(2) for 10 s, was found to efficiently exhibit a week-long sustained release in vitro, and applied in vivo. The remaining amount or plasma concentration of PR after s.c. administration of the implant tablet to rats demonstrated that the implant tablet showed a week-long sustained release in vivo. The present implant tablet is suggested to be useful as a drug delivery system for supplying drugs for approximately 1 week.

Animals↗

Quantitative determination of captopril and prednisolone in tablets by FT-Raman spectroscopy.

A procedure for the quantitative determination of captopril and prednisolone in commercial tablets based on partial least squares (PLS) and principal component regression (PCR) treatment of FT-Raman spectroscopic data is described. In the studied medicines active pharmaceutical ingredients (APIs) constitute 4.2-16.7% of the tablet mass. Results obtained from calibration models built using unnormalised spectra were compared with the values found when an internal standard was added to each sample and the spectra were normalised by its selected band intensity at maximum or integrated. To appraise the quality of the models the relative standard error of predictions (RSEPs) were calculated for calibration and testing data sets. For captopril determination these were 1.8-2.2% (2.1-2.3%) and 2.7-3.1% (2.7-3.6%), respectively for the different PLS (PCR) models. For prednisolone these errors amounted to 1.8-2.1% (2.6-3.5%) and 3.2-3.7% (3.7-5.9%), respectively. Three commercial preparations of captopril containing 12.5mg and one 25mg of API per tablet were quantified using developed models. Found captopril contents, calculated versus results of iodometric titration, was equal 99.2-101.2% (99.2-102.0%), for the different PLS (PCR) calibration models and the different preparations. Quantification of prednisolone tablets, declared content 5mg per tablet, on the basis of PLS (PCR) models gave API amount, calculated versus results of UV-vis method, in the 99.0-101.0% (98.0-102.0%) range.

Algorithms↗