Hydroxypropyl Methylcellulose Tablets Research Articles

Effect of Formulation Variables on Dissolution Profile of Diclofenac Sodium from Ethyl- and Hydroxypropylmethyl Cellulose Tablets

AbstractThe effects of formulation variables on the release profile of diclofenac sodium from ethyl cellulose (EC) and hydroxypropylmethyl cellulose (HPMC) matrix tablets were investigated. With increase in viscosity of ethyl cellulose used in nonaqueous granulation, a decrease in drug release from the tablets was observed, while the percentage of fines articles passed through 60 mesh) in the granulation had a significant effect on the dissolution profile. Granules containing 15% fines exhibited slow release of the drug in comparison to those containing 30% fines with EC matrices. An analysis of kinetics of drug release from hydrophobic EC matrix showed Fickian diffusion regulated dissolution. Drug release from HPMC tablets followed an apparent zero-order kinetics.

Design and evaluation of sustained-release and buccal adhesive propranolol hydrochloride tablets

The release of propranolol hydrochloride incorporated into sustained-release and buccal adhesive tablets was studied in vitro. The formulation containing 20% hydroxypropyl methylcellulose (HPMC) yielded good sustained-release matrix tablets. Buccal adhesive controlled-release tablets were prepared by compression of HPMC with polycarbophil (PAA), which served as the bioactive adhesive compound. The release behaviour of buccal adhesive tablets was found to be non-Fickian. The adhesion force was significantly affected by the mixing ratio of HPMC and PAA in the tablet and the weakest adhesion force was observed at the ratio of 1:1 (HPMC:PAA). Interpolymer complex formation was confirmed between HPMC and PAA in acidic medium by turbidity, viscosity and FT-IR measurements. The kinetics of sustained-release and buccal adhesive tablets of propranolol were examined in nine healthy volunteers. Conventional propranolol (Dideral®) was also studied for comparison purposes. As compared to conventional propranolol (40 mg), a single dose of 20% HPMC (160 mg) produced a smoother plasma level profile, with lower and delayed peak times. Dose corrected AUC 0–8 values were greater after Dideral® than after 20% HPMC (168.7 ± 80.3 vs 97.3 ± 36.1 ng h ml −1 p < 0.05). The buccal delivery of propranolol caused ulceration and serious irritation that took weeks to heal. There was no significant difference ( p > 0.05) in the AUC 0–4 values between 20% HPMC and buccal adhesive tablets.

The Influence of Binding Solvents on Drug Release from Hydroxypropyl Methylcellulose Tablets

AbstractThe objective of this project was to evaluate the influence of binding solvents on drug release from hydroxypropylmethylcellulose (HPMC) tablets. The model drug used for this study was Indomethacin. HPMC 4000 and lactose were used to prepare the tablets. The experiment was designed based on a 3×5 factorial design. The drug/polymer ratio was examined at three levels, 2:1, 1:1, and 1:2. At each of these levels the solvent effects were examined at five levels. Within these five levels, four different combinations of water and ethanol (100% water, 60% water 40% ethanol, 40% water 60% ethanol, and 20% water 80% ethanol) were compared with the fifth level which is a matrix tablet prepared by direct compression without any solvents. The dissolution rates of the tablets were monitored using a rotating paddle dissolution apparatus. The cumulative percent of drug dissolved from the three matrix tablets are not significantly different (p>0.05). The cumulative percent of drug dissolved at 2 hr from the variou...

Fickian and Relaxational Contribution Quantification of Drug Release in a Swellable Hydrophillic Polymer Matrix

Hydroxypropylmethylcellulose (HPMC) is becoming very popular in the formulation of controlled release tablets, mainly because of its hydrophillic and swelling properties. In HPMC tablet matrix systems, the drug release occurs mainly by Fickian diffusion and by polymer relaxation. The amount of drug released by these two phenomena was quantified by applying a heuristic model recently proposed. Recent studies show that it is possible to modify the kinetics of drug release by restricting matrix swelling. The aim of this study is to present some new evidence that tends to confirm these findings and to quantify the Fickian and case II relaxational contribution of drug release by using a PCNONLIN computer software package. Results obtained show a direct relationship between releasing areas and the amount of drug dissolved. Tablets with matrix swelling restrictions exhibit a shift towards drug release by relaxational mechanism, which makes this technique a useful tool when a shift towards constant drug release i...

Pharmacokinetics and dose proportionality of D2-agonist MK-458 (HPMC) in parkinsonism.

To investigate the pharmacokinetic profile, bioavailability, and dose proportionality of the D2-agonist MK-458 (hydroxypropylmethylcellulose tablet, a sustained release formulation), a 4-period crossover study was conducted in 10 patients with mild to moderate Parkinson's disease (mean age = 63 y; 1 woman, 9 men). Following a titration phase to induce tolerance, each patient was given single oral doses of 6, 12 and 18 mg and a single intravenous 40 micrograms dose (5 micrograms/h over 8h). The maximum concentrations of MK-458 observed in plasma after oral administration were 139, 240 and 344 ng/L for the 6, 12 and 18 mg doses, respectively, and occurred after 8.0, 9.0 and 5.5 h, respectively. Mean areas under the plasma concentration-time curves were 1728, 2849 and 5484 ng/L.h, respectively. The mean plasma half-life was 3.8 h and mean plasma clearance was 3390 ml/min (203.4 L/h). The bioavailability (approximately 5%) was very similar for the 3 tablet formulations tested. The disposition of MK-458 was independent of the dose over the range of doses studied.

Importance of drug type, tablet shape and added diluents on drug release kinetics from hydroxypropylmethylcellulose matrix tablets

The dissolution of 7 drugs from hydroxypropylmethylcellulose (HPMC) matrices have been examined to determine the time exponent ( t n ) required to produce linear dissolution profiles. A value of n = ~ 0.67 was obtained for time-dependent release for soluble drugs, the precise values being 0.71, 0.65, 0.67 and 0.64 for promethazine hydrochloride, aminophylline, propranolol hydrochloride and theophylline, respectively. The insoluble drugs, indomethacin and diazepam, displayed values of n = 0.90 and 0.82 indicating a near zero-order release. Matrices containing tetracycline hydrochloride, however, showed a value of n = 0.45 and displayed complex release patterns and lower release rates than anticipated on the basis of solubility. Replacement of HPMC by calcium phosphate or lactose increased the dissolution rates of promethazine hydrochloride although the values of n were unchanged. Differences in release rates between lactose and calcium phosphate replacement occurred only when matrices contained high levels of the diluents. A straight line relationship existed between release rates and tablet surface area for HPMC tablets containing promethazine hydrochloride.