Sodium phosphate dosage

Avastin Avastin is used for the treatment of colorectal cancer. It is supplied in 100 and 400 mg dosages. The 100 mg formulation consists of 240 mg a,a-trehalose dihydrate, 23.2 mg sodium phosphate (monobasic, monohydrate), 4.8mg sodium phosphate (dibasic, anhydrous), 1.6mg polysorbate 20 and water-for-injection. 

Therapeutic formulations contain a recombinant form of IFN-a (either interferon alfa-2a or interferon alfa-2b). These are available as powders for reconstitution or as prefilled injection pens. The drug is administered by subcutaneous injection (or intravenous for reconstituted powder formulations) and intramuscular injection. The dosage is usually stated as units per millilitre (refer to BNF for various preparations and dosages). Powder formulations of interferon alfa-2b also contain glycine, sodium phosphate (mono- and dibasic) and human albumin prefilled pens contain sodium chloride, edetate disodium, polysorbate 80 and m-cresol as a preservative. 

Hydrocortisone and hydrocortisone cypionate (Cortef) may be administered orally. Hydrocortisone sodium phosphate may be administered by IM, SC, or IV injection, or by IV infusion, q. 12-hour interval. Hydrocortisone sodium succinate (A-hydroCort, Lifocort, Solu-Cortef) may be administered by IM or rV injection or IV infusion q. 2 to 10 hours, depending on the clinical situation. Hydrocortisone acetate is a suspension that may be administered by intra-articular, intrasynovial, intrabursal, intralesional, or soft tissue injection. It has a slow onset but a long duration of action. The injectable forms are usually used only when the oral dosage forms cannot be used (see also Table 11). 

Dexamethasone, prednisolone and hydrocortisone are systemically active via the rectal route. The best chemical form of the active substance must be chosen and a dosage form that provides good release of the active substance. A corticosteroid as salt in solution is often optimal for an enema and the preparation is easy. As a solution in water it avoids problems such as release from a fatty base and subsequent dissolution. Dexamethasone and prednisolone for instance are used as sodium phosphate salts. Conversion and factorisation must not be forgotten. For stability reasons... 

Hydrocortisone sodium succinate is the available salt of hydrocortisone. It is not suitable for enemas because it is very unstable in aqueous solution. Alternatives are hydrocortisone or hydrocortisone acetate in a suspension enema or a suppository. For a systemic effect hydrocortisone is preferred because of its better solubility. Administration in a fatty suppository satisfies the requirements [51]. A suspension enema seems the better alternative, but literature does not provide a formula for a stable product. Therefore, in an enema the use of prednisolone or dexa-methasone sodium phosphate is preferred. Local effect may be achieved with hydrocortisone acetate, sometimes used in suppositories in the treatment of haemorrhoids. However, for this indication hydrocortisone acetate processed in a fatty cream is preferred. That dosage form minimises absorption as little cream will reach the rectum. 

Rao et al. [45] determined primaquine phosphate, in pharmaceutical dosage forms, by using a colorimetric method. Powdered tablets containing the equivalent of 100 mg of primaquine phosphate were heated with 25 mL of water for 10 min, the solution was cooled and filtered, and 10 mL portion of the filtrate was diluted 10-fold with water. A 5-mL portion of this solution was mixed with 5 mL of pH 5 buffer solution, 1 mL of 0.08%. amidopyrine solution in aqueous 95% alcohol and 2 mL of aqueous 0.1% sodium periodate. After 10 min, 0.5 mL of aqueous sodium metabisulfite solution was added and the absorbance was measured at 580 nm. Beer s law was obeyed between 4 and 43 pg/mL of primaquine phosphate. Recoveries were quantitative. 

Buffers contain mixtures of weak acids and their salts (i.e., the conjugate bases of acids), or mixtures of weak bases and their conjugate acids. Typical buffer systems used in pharmaceutical dosage forms include mixtures of boric acid and sodium borate, acetic acid and sodium acetate, and sodium acid phosphate and disodium phosphate. The reason for the buffering action of a weak acid, HA (e.g., acetic acid) and its ionized salt, A" (e.g., sodium acetate) is that A" ions from the salt combine with the added hydrogen ions, removing them from solution as undissociated weak acid. 

Absorption of phenytoin is highly dependent on the formulation of the dosage form. Particle size and pharmaceutical additives affect both the rate and the extent of absorption. Absorption of phenytoin sodium from the gastrointestinal tract is nearly complete in most patients, although the time to peak may range from 3 to 12 hours. Absorption after intramuscular injection is unpredictable, and some drug precipitation in the muscle occurs this route of administration is not recommended for phenytoin. In contrast, fosphenytoin, a more soluble phosphate prodrug of phenytoin, is well absorbed after intramuscular administration. 

Hydrocortisone sodium succinate or phosphate in doses of 100 mg intravenously is given every 8 hours until the patient is stable. The dose is then gradually reduced, achieving maintenance dosage within 5 days. 

Panderi and Parissi-Poulou developed a microbore liquid chromatographic method for the simultaneous determination of benazepril hydrochloride and hydrochlorothiazide in pharmaceutical dosage forms [30]. The use of a BDS C-18 microbore analytical column was found to result in substantial reduction in solvent consumption and in increased sensitivity. The mobile phase consisted of a mixture of 25 mM sodium dihydrogen phosphate buffer (pH 4.8) and acetonitrile (11 9 v/v), pumped at a flow rate of 0.4 mL/min. Detection was effected at 250 nm using an ultraviolet absorbance detector. The intra- and inter-day relative standard deviation values were less than 1.25% (n = 5), while the relative percentage error was less than 0.9% (n = 5). The detection limits obtained according to the IUPAC definition were 0.88 and 0.58 pg/mL for benazepril hydrochloride and hydrochlorothiazide, respectively. The method was applied to the quality control of commercial tablets and content uniformity test, and proved to be suitable for rapid and reliable analysis. 

The dosage form is a powder for solution that is reconstituted in sterile water. Excipients are human albumin, sodium chloride, and phosphate buffer. The solution can be stored at 2 to 8°C and should be di.scarded if it freezes. The lyophilized powder expires in IS months. After reconstitution, the solution should be used within 6 hours. The solution should not be. shaken because of the albumin content. 

Chemistry (Fig. 8.28). Riboflavin has a characteristic flavin ring system, which gives it unique spectroscopic and instability properties. There are two commercial forms. Riboflavin itself is poorly water soluble (1 g/10,000 mL) and is limited to oral dry dosage forms. Riboflavin phosphate, as the sodium salt, is very water soluble at 100 mg/mL and is widely used in dry and liquid dosage forms. 

Many synthetic substances to be used in solid dosage form are too limited in solubility to be therapeutically effective. The desirable solubility for an oral solid is suggested to be more than 1 mg/ml (0.1%). To increase solubility, a weak basic drug such as an amine may react with respective mineral acids to form salts, that is, hydrochloride (more than 40% of the salt marketed), sulfate, or phosphate. For an amine with two functional groups, a mono- or dihydrochloride salt may be formed, depending on the condition and amount of hydrochloric acid added. For an organic acid, a salt with sodium or potassium can easily be formed. Because a molecule of salt is polar, it should be freely soluble in water, reaching a therapeutic solubility level. The other types of acids commonly used for salt formation with a weak base are sulfonic acids and carboxylic acids. 

The first issue in bioburden determination that merits validation is the choice of fluid used in preparatory stages of removal of microorganisms from devices and for suspending, dissolving, and diluting dosage forms. Phosphate buffer pH 7.2. buffered sodium chloride-peptone solution pH 7.0, and lactose broth are recommended in the various compendia. Saline, Rtnger s solution, and... 

Rapid form dissociation and precipitation of known forms of the parent celecoxib was observed in 0.1 N HCl, SGF, 0.02 N HCl, pH 6.5 phosphate buffer and pH 6.5 phosphate buffer with sodium dodecyl sulfate (SDS). The initial dissolution rate was found to be superior for the co-crystal versus the stable form of the parent compound, but rapid conversion to aggregated crystalline celecoxib made this co-crystal a poor candidate for direct use as a dosage form. This initial dissolution advantage was exploited further by formulating the co-crystal with PVP-K30 and the ionic surfactant SDS. Using this combination of excipients, the co-crystal was repeatedly observed to precipitate as a poorly crystalline mixture of metastable celecoxib form 4 and amorphous material. Although the co-crystal was not tested in vivo, the in vitro performance improvements are consistent with improvements observed in other celecoxib formulations with demonstrated in vivo advantages over Celebrex . 

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