Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0149958 (complex partial seizures)
 2,563 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

An orally applicable nifedipine-loaded core tablets was coated using high viscosity grade HPMC (100,000 cps) in ethanol/water cosolvent. The release of coated tablet was evaluated using USP paddle method in 900 ml of simulated gastric fluid (pH 1.2) for 2 h followed by intestinal fluid (pH 6.8) for 10 h. The surface morphologies using scanning electron microscope and photo-images using digital camera of coated tablet during the release test were also visualized, respectively. The viscosity of hydro-alcoholic HPMC solution largely decreased as the amount of ethanol increased. There was no significant difference in viscosity among plasticizers used. The distinct and continuous coated layer was observed using scanning electron microscope. However, the surface morphologies were highly dependent on HPMC concentration and ratio of coating solvents. The higher ratio of ethanol/water gave a longer lag time prior to drug release. Lag time also increased as a function of the coating levels based on weight gains due to increased thickness of coated layer. Lag time is inversely correlated with HPMC concentration in ethanol/water (5:1) cosolvent. As the HPMC concentration slightly decreased from 3.8 to 3.2% in hydroalcoholic coating solution, a large increase of lag time was observed. As the swelling (mixing) time of high viscosity grade HPMC in ethanol/water cosolvent increased from 1 to 5 h, the release rate was decreased due to enough plasticization of polymer. Based on photo-imaging analysis, the coated tablet was initially swelled and gelled without erosion and disintegration over 5 h. The disintegration of the coated tablet was occurred approximately 7 h after dissolution, resulting in pulsed release of drug. The high viscosity grade HPMC can be applicable for polymeric coating after careful selection of solvent systems. The release behavior and lag time could be controlled by coating conditions such as HPMC concentration, ethanol/water ratio as a coating solvent, coating level and swelling (mixing) time of coating solution. The current time-controlled release tablet coated with high viscosity grade HPMC with a designated lag time followed by a rapid release may provide an alternative to site specific or colonic delivery of drugs. In addition, the release behavior can be matched with body's circadian rhythm pattern in chronotherapy.
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PMID:Release behavior and photo-image of nifedipine tablet coated with high viscosity grade hydroxypropylmethylcellulose: effect of coating conditions. 1507 87

As the main intent of delivering maximum concentration of drug available from the dosage form, an oral compression coated tablet (CCT) was intended to develop with a predetermined lag time of 6 hrs before immediate release of drug to target circadian rhythms of rheumatoid arthritis. Solid dispersions are promising approach to enhance drug release, which later will be developed as core tablet formulation and compression coated with polyethylene oxide (PEO WSR 303). Solid dispersions were formulated with different ratio of drug and carrier (sucrose fatty acid esters 1811) using solvent evaporation and melt granulation technique, optimized solid dispersion was formulated as core tablet with different diluents. Optimized core tablet was compression coated with PEO WSR 303 along with a channeling agent (DCL 21, mannitol, HPMC 5 cps and starch 1500). Lag time before immediate release of drug was markedly dependent on weight ratios of polymer and channeling agent used, which ranged from 4 to 12 hrs. Optimized solid dispersion (S9) was used for formulating optimized core tablet formulation (C8). CCT (T8) prepared with core tablet (C8) along with mannitol provided a lag time of 6 hrs with minimum concentration of channeling agent used, which was also supported from the permeability study results. Incompatibility and characterization was confirmed from DSC, XRD, FTIR and SEM studies. Unaltered Cmax and AUC0-t but delayed Tmax following oral ingestion of optimized formulation (T8) to human volunteers indicated clear lag time before immediate release of drug, which is suitable for treating rheumatoid arthritis following circadian rhythm.
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PMID:Chronotherapeutic drug delivery from indomethacin compression coated tablets for early morning pain associated rheumatoid arthritis. 2297 84