Tablet coated

The advantages of this type of system are that the release rates are independent of the dmg properties, macromolecules and ionic species may be dehvered, fluxes may be high, and release rates are not dependent upon environmental conditions such as pH. The disadvantages are that the system is subject to dose-dumping if it is chewed. It is also more expensive to formulate than coating tablets, and there is a possibiUty of hole plugging. 

DIGESTIVE ENZYMES. When digestive enzymes are given in capsule or enteric-coated tablet form, the nurse... 

If the tablet has a coating (enteric-coated tablets), swallow it whole. Do not chew or crush the tablet. 

Neural networks have also been used in Slovenia, to model the release characteristics of diclofenac [52] in China, to study release of nifedipine and nomodipine [53] and in Yugoslavia to model the release of aspirin [54], More recently, work in this area has been extended to model osmotic pumps in China [55] and enteric coated tablets in Ireland [56],... 

For parenteral use, the antibiotic is packed in sterile vials as a powder (reconstituted before use) or suspension. For oral use it is prepared in any of the standard presentations, such as film-coated tablets. Searching tests are carried out on an appreciable number of random samples of the finished product to ensure that it satisfies the stringent quahty control requirements for potency, purity, freedom horn pyrogens and sterility. 

Lakes are prepared by adsorption or precipitation of a soluble dye on an insoluble substrate (e.g., alumina). They are useful in fatty products that have insufficient moisture to dissolve dyes (coated tablets, cake mixes, hard candies, chewing gum). Lakes are insoluble in most solvents including water, have high opacity, are easily incorporated in dry media, and show higher stability to light and heat. They are effective colorants for candies, pills, fats, and oils. The main characteristics and differences between lakes and dyes are well documented. ... 

Sulfasalazine Azulfidine Azulfidine Entabs Sulfazine Sulfazine EC Immediate-release or enteric-coated tablets 500 mg 2-6 g Colon... 

Syrup/suspension/ solution Extended-release/ enteric-coated tablets Faster rate of absorption 100% Delayed absorption 60-90% Faster rate of absorption Delayed absorption 89% of the suspension and less than regular-release tablets Unknown NA Faster rate of absorption than tablets Extended-release 90% of intravenous dose. Delayed-release 81-90% of intravenous dose Delayed absorption with delayed-release tablets valproate is rapidlyconverted to VPA in the stomach, then is rapidly and almost completely absorbed from the Gl tract NA NA... 

A drug should always be ingested with a cup of water ( 8 oz) to insure easy transit down the esophagus and to provide fluid for disintegration and dissolution. Whether or not the drug should be taken on an empty stomach (e.g., enteric-coated tablets) or with food will depend upon the specific drug as noted above. 

The dose uniformity of tablets can be determined by two different general approaches the weight variation between a specified number of tablets or the extent of drug content uniformity. The USP permits the latter approach in all cases. Moreover, drug content uniformity must be measured for coated tablets because... 

T Dahl, ILT Sue, A Yum. The effect of pancreatin on the dissolution performance of gelatin-coated tablets exposed to high-humidity conditions. Pharm Res 8 412-414,1991. 

M Aikman, L Augsburger, I Berry et al. Collaborative development of two-tiered dissolution testing for gelatin capsules and gelatin-coated tablets using enzyme-containing media. Pharmacop Forum 24(5) 7045-7050, 1998. 

Enteric-coated tablets or capsules of garlic are better absorbed since an active ingredient, allicin, is acid labile. The tablets or capsules bypass the stomach and release their contents in the alkaline medium of the small intestine [4],... 

In addition to coating tablets, asymmetrical membrane systems can also be prepared as capsules or multiparticulates. 

WA Ritchel, A Sabouni, SH Gehrke, ST Hwang. Permeability of [3H]water across a porous polymer matrix used as a rate-limiting shell in compression-coated tablets. J Controlled Release 12 97-102, 1990. 

Other industrial applications of the concept include that for coating tablets in the pharmaceutical industry (Wurster et al. 1965), for drying of... 

Garlic supplements - powder tablets or capsules, steam-distilled oil, vegetable oil macerate extract, or extract aged in dilute alcohol - are widely available and are taken by millions. Since the active principle, allicin, is not present in garlic bulb, the supplements rely on the presence of precursor alliin and enzyme alliinase. In tests on 24 commercial brands of enteric-coated tablets, all except one gave low dissolution allicin release 83% of the brands released less than 15% of their potential allicin.78,79 Relevant factors were impaired enzyme activity caused by excipients and slow tablet disintegration. Caveat emptor ... 

Oral pancreatic enzyme supplements are available as powders, uncoated or coated tablets, capsules, enteric-coated spheres and microspheres, or enteric-coated microtablets encased in a cellulose or gelatin capsule (Table 28-2). Microencapsulated enteric-coated products are not superior to recommended doses of conventional non-enteric-coated enzyme preparations. The quantity of active lipase delivered to the duodenum appears to be a more important determinant in pancreatic enzyme replacement therapy than the dosage form. GI side effects appear to be dose related but occur less frequently with enteric-coated products. 

The enteric-coated tablet divalproex sodium causes fewer GI side effects. It is metabolized in the gut to valproic acid. When switching from Depakote to Depakote-ER, the dose should be increased by 14% to 20%. Depakote ER may be given once daily. 

Verapamil Verelan Calan, Isoptin Capsule 120, 180,240, 360 mg Film-coated tablet 40, 80, 120 mg Extended-release tablet 120, 180, 240 mg 80-480 mg/day combination with other drugs (e.g., carbamaze-pine, valproate, antipsy-chotics). L-type Ca+ channels Alters Ca+-Na+ (change Decreases 5-HT, DA, and endorphin activity... 

These authors14 later report using the GC method for enteric coated tablets of erythromycin, giving a recovery of 99.8% and a coefficient of variation of 2.3% based on placebo tablets spiked with erythromycin. 

Baugh and co-workers exposed solutions of phenylbutazone to the light of a projector lamp in the presence of typical dyes used to colour sugar-coated tablets. Erythrosine sodium photosensitized decomposition of the drug via, it was suggested, singlet oxygen [134]. 

Enteric coated tablets are designed to resist the acidic environment in the stomach and release the medication in the small intestine. If such tablets are broken, their enteric properties may be lost. Therefore, do not break them. 

The flow-through cell is applicable not only for the determination of the dissolution rate of tablets and sugar-coated tablets, but has also been applied to suppositories, soft-gelatin capsules, semisolids, powders, granules, and implants. A small volume cell containing the sample solution is subjected to a continuous stream of dissolution media. The dissolution... 

Figure 5 Magnetic moment images of an enteric-coated tablet containing a small amount of magnetized ferric oxide. Left-hand panel shows three sequences in a single volunteer viewed from the front. The right-hand panel shows the same sequences viewed from the top. (Courtesy of Prof. Dr. W. Weitschies.)...

Perkins AC, Wilson CG, Frier M, Vincent RM, Blackshaw PE, Danserau RJ, Juhlin KD, Bekker PJ, Spiller RC. Esophageal transit of risedronate cellulose-coated tablet and gelatin capsule formulations. Int J Pharm 1999 186 169-175. 

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