Tablets, compound

Aspinn possesses a number of properties that make it an often recommended drug It is an analgesic effective m relieving headache pain It is also an antiinflammatory agent providing some relief from the swelling associated with arthritis and minor injuries Aspinn IS an antipyretic compound that is it reduces fever How aspmn does all this was once a mystery but is now better understood and will be discussed m Section 26 6 Each year more than 40 million lb of aspirin is produced m the United States a rate equal to 300 tablets per year for every man woman and child... 

Many pharmaceutical compounds contain chromophores that make them suitable for analysis by UV/Vis absorption. Products that have been analyzed in this fashion include antibiotics, hormones, vitamins, and analgesics. One example of the use of UV absorption is in determining the purity of aspirin tablets, for which the active ingredient is acetylsalicylic acid. Salicylic acid, which is produced by the hydrolysis of acetylsalicylic acid, is an undesirable impurity in aspirin tablets, and should not be present at more than 0.01% w/w. Samples can be screened for unacceptable levels of salicylic acid by monitoring the absorbance at a wavelength of... 

Choline salicylate ((2-hydroxyethyl)trimethylammonium salicylate) is contained in a list of safe and effective compounds (30). Choline salicylate [2016-36-6] (5) is the only liquid salicylate preparation available and is often useful for arthritic patients who have difficulty swallowing tablets. 

The copolymers are insoluble in water unless they are neutralized to some extent with base. They are soluble, however, in various ratios of alcohol and water, suggesting appHcations where deUvery from hydroalcohoHc solutions (149) but subsequent insolubiUty in water is desired, such as in low volatile organic compound (VOC) hair-fixative formulations or tablet coatings. Unneutralized, their Ts are higher than expected, indicating interchain hydrogen bonding (150). 

ChlorinatedIsocya.nura.tes. The cyanuric acid-based sanitizers, introduced for pool use in 1958, are stable crystalline compounds with moderate-to-high available CI2. Sodium dichloroisocyanurate (Dichlor), sold in granular form, dissolves rapidly, whereas trichloroisocyanuric acid (Trichlor) dissolves very slowly and is widely used in the form of tablets or sticks in feeders, floating devices, or in the pool skimmer. 

Vapor-phase inhibitors are volatile compounds that adsorb onto metal surfaces, and retard or prevent corrosion by a variety of mechanisms (37). Inhibitors such as dicyclohexamine nitrate [3882-06-02] can protect a variety of metals such as steel, aluminum, and tinplate. A number of vapor-phase inhibitors are commercially available as powders or tablets. However, vapor-phase inhibitors attack nonferrous metals to varying degrees, thus the manufacturers recommendations should be checked before appHcation. The system to be protected must be closed to maintain the volatile compound, but objects as large as the interior of an ocean-going tanker have been treated by this technique. 

It has a water solubility of about 55%. It may ba compounded in the form of tablets, for oral administration, or may be prepared in solution for distribution in ampoules. For tha manufacture of solutions for packaging in ampoules. It is more convenient to simply dissolve tha theophylline and tha butanol amine in water, without going through the intermediate step of separating the crystalline salt. 

The permeability of the films to paracetamol as a model compound was dependent on film composition and was markedly increased after exposure to pectinolytic enzymes, used to mimic conditions in the colon. Similar formulations, apphed as a film coat to tablets, were used with colonic conditions for an increased release rate [242],... 

The number of samples to be processed for every batch produced six samples of 13 tablets each are taken at prescribed times after starting the tablet press (10 tablets are ground and well mixed (= compound sample), two average aliquots are taken, and each is extracted) the additional three tablets are used for content uniformity testing this gives a total of 6 (2 -t- 3) = 30 determinations that have to be performed. 

In Fig. 4.39, results for spiked placebo and for the verum tablets are given for compound A (bold lines) and B all horizontal bars should be at 100%, and the vertical lines should be centered at the same height. The gray trendlines, particularly for the LO- and Hl-range A-values indicate a systematic difference in response between tbe calibration solutions and the spiked placebo tablets (extraction efficiency, interference, etc.). For same ranges, the verum-tablets assays either underestimate the content of A by 4—5%, or A is underdosed. For compound A the repeatability figures are as follows (%-of-nom-inal, see file Fig4 39.dat), see Table 4.36. 

Figure 4.39. Variability of back calculated concentrations Concbc- For each concentration range five calibration points were measured, over which a separate regression was run (not shown). Placebo tablets were spiked to the same concentrations and measured in triplicate (short horizontal lines gray trend lines in background). Ten repeat determinations of actual product (vertical bars = Mean + SD) were done. The bold lines pertain to compound A in all concentration ranges, the thin lines to compound B (middle concentration range only).

Example 60 If compound samples that were actually composed of five individual tablets had been analyzed instead of the spiked matrix, the CV would be expected to be larger than 0.5% on account of the additional manufacturing error, but by a factor Vs = 2.2 lower than the content uniformity CV. (Cf. Eq. (1.5).) Since the average CV for CU was found to be -1.76% ( 1.97, 1.28, resp. 1.95%), this would have to be in the region of about 1.76/2.2 = 0.8, which is still well within the range of accepted instrumental noise. 

A tablet containing two drug compounds, A and B, is being scaled up from kilogram to half-ton batches in preparation for a regulatory submission. The applicable specifications and sample work-up methods are... 

Assay 90-110% of label claim (pick 20 tablets at random grind and mix weigh an amount of powder corresponding to five tablets dissolve compound sample and centrifuge excipients run a HPLC analysis on an aliquot of the supernatant), and... 

A second group of compounds, formed by N-chloro derivatization of heterocyclic compounds containing a nitrogen in the ring, includes the sodium and potassium salts of dichloroisocyanuric acid (e.g. NaDCC). These are available in granule or tablet... 

Common pharmaceutical products of olibanum and salai guggul are tablets prepared from dried extracts of boswellic adds, which are obtained by processes involving treatment of the resins with alkali and acid. The stress involved in this treatment is expected to lead to alteration of some triterpenes as, e.g., the conversion of the unstable 3-(9-acetyl-ll-hydroxy-[3-boswellic acid (compound 12) to the stable compound 3-(9-acetyl-9,ll-dehydro-[3-boswellic acid (compound 13). Two-dimensional TLC is an excellent means of observing this conversion [5]. For verification of this process, the substances have to be isolated by PLC and identified by GC-MS. 

The phenomenon of pseudopolymorphism is also observed, i.e., compounds can crystallize with one or more molecules of solvent in the crystal lattice. Conversion from solvated to nonsolvated, or hydrate to anhydrous, and vice versa, can lead to changes in solid-state properties. For example, a moisture-mediated phase transformation of carbamazepine to the dihydrate has been reported to be responsible for whisker growth on the surface of tablets. The effect can be retarded by the inclusion of Polyoxamer 184 in the tablet formulation [61]. 

Few tablets intended for oral administration are totally soluble in aqueous media, but if such a product is needed, then soluble excipients are employed. These include dextrose, lactose, mannitol, and sodium chloride, with the last of these sometimes acting as its own lubricant. Urea may also be used, but due to its known pharmacological effects, it is less desirable than the other soluble compounds cited. 

Phyllosilicates, in addition to talc and silica, have recently been evaluated for their use as tableting excipients. These compounds include the smectites, pa-lygorskites, and sepiolites [85a]. Although they show some promise, current levels of metallic impurities are currently too high for use in pharmaceutical preparations. 

Another new development has been the application of oral absorption promoters. These materials are designed to enhance the oral bioavailability of many compounds and improve variable absorption. However, many of these compounds are hydrophobic in nature and cause difficulty during tableting itself. The challenge for formulators is to arrive at clever solutions to the process problems while retaining material performance. 

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