TOPICAL phosphate

Wasson JR, Woltermann GM, Stoklosa HJ (1973) Transition metal dithio- and diseleno-phosphate complexes in inorganic chemistry. Topics in Current Chemistry, Springer, Berhn Fleidelberg New York, 35 65... 

T. R. French. Design and optimization of phosphate-containing alkaline flooding formulations Topical report. US DOE Fossil Energy Rep NlPER-446, NIPER, February 1990. 

Monsanto 1987a, 1987b, 1989), Cellulube 220 (Carpenter et al. 1959), and a triaryl phosphate hydraulic fluid (Siegel et al. 1965). In addition, no evidence of renal damage was observed following intermediate-duration exposure of rats to oral doses of Pydraul 90E (Monsanto 1979), rabbits to topical cyclotriphosphazene (Kinkead et al. 1989c, 1990), or rabbits to topical Cellulube 220 (Carpenter et al. 1959). 

Suspension. If the drug is not sufficiently soluble, it can be formulated as a suspension. A suspension may also be desired to improve stability, bioavailability, or efficacy. The major topical ophthalmic suspensions are the steroid anti-inflammatory agents prednisolone acetate, dexamethasone, fluorometholone, and rimex-olone. Water-soluble salts of prednisolone phosphate and dexamethasone phosphate are available however, they have a lower steroid potency and are poorly absorbed. 

Several papers related to the present topic have appeared in the literature after the submission of our manuscript, indicative of the great interest in this area. A peroxo-bridged dinuclear cobalt(III) complex, similar to 9, has been shown to efficiently hydrolyze the nonactivated methyl phenyl-phosphate [67]. Using 180-labeled D20 or 02, incorporation of 180 to the product was only observed from the solvent, indicating a true hydrolytic mechanism. 

An overview is provided of ongoing risk assessments on halogenated phosphate ester flame retardants in Europe. On the basis of the so-called second and fourth Priority lists on Existing Chemicals (Council Regulation No793/93) three chlorinated phosphate ester flame retardants are selected. The selection is based on their hazard profile, volume and use pattern. The three substances involved are TCPP, TDCP and TCEP (Antiblaze V6 from Albemarle is also involved but, due to confidentiality, is not discussed. An outline is provided from a European point of view on topics such as methodology of risk analyses, data-gaps and worst case approach, industry involvement, downstream participation and possible impact of final report on industry. 2 refs. 

The stereochemistry of optically active phosphorus thio-acids has been reviewed2 and published lectures have covered such topics as phosphate and phosphonate compounds based on adamantane3 and AW-dihalogeno-amides of phosphoric acids.4... 

Magnetic resonance techniques have again been popular for studying enzymes which are involved in phosphate hydrolysis and transfer. 31P or 19F N.m.r.1-2 and spinlabelling3 have all been used to study the interaction of substrates with these enzymes, while affinity labelling4 5 6 7 is another technique which has been used to obtain information about the sequence and conformation of amino-acid chains at the active sites of enzymes. Recently, these experimental methods have been applied to the study of cell membranes,6-7 and these are mentioned in a new series of books concerned with enzymes in biological membranes.8 A new journal, Trends in Biochemical Sciences, which contains concise, up-to-date reviews on these and other topics is published by Elsevier on behalf of the International Union of Biochemistry. 

Solutions are used topieally as well as internally. Examples of eompounded liquids include topicals (wart solutions), oral syrups and elixirs, nasal solutions, otic solutions, iontophoretic solutions (dexamethasone sodium phosphate), and many others (Table 5). 

Glucocorticoids are available in a wide range of preparations, so that they can be administered parenterally, orally, topically, or by inhalation. Obviously the oral route is preferred for prolonged therapy. However, parenteral administration is required in certain circumstances. Intramuscular injection of a water-soluble ester (phosphate or succinate) formed by esterification of the C21 steroid alcohol produces peak plasma steroid levels within 1 hour. Such preparations are useful in emergencies. By contrast, acetate and tertiary butylacetate esters must be injected locally as suspensions and are slowly absorbed from the injection site, which prolongs their effectiveness to approximately 8 hours. 

P.P. Hagen, R.G. Rozier, J.W. Bawden, The caries-preventive effect of full- and halfstrength topical acidulated phosphate fluoride, Pediatr. Dent. 7 (1985) 185-191. 

H.S. Horowitz, J. Doyle, The effect on dental caries of topically applied acidulated phosphate-fluoride Results after three years, J. Am. Dent. Assoc. 82 (1971) 359-365. 

Dexamethasone (DEXONA) 0.5-5 mg/day oral, 4-20 mg/day IM/IV, 0.1% topical (skin cream) as dexamethasone sodium phosphate and trimethyl acetate... 

Synthetic glucocorticoids are prednisolone, prednisone, methylprednisolone, dexamethasone, betamethasone and triamcinolone (Table 13.2). Hydrocortisone is available as either succinate or phosphate salts for oral and intravenous administration. It is the drug of choice when a rapid effect is required, e.g. acute adrenal insufficiency, or as peri-operative replacement therapy. Prednisolone can also be given intravenously. It has about 0.8 of the mineralocorticoid activity of hydrocortisone. Prednisone is a prodrug that is converted to prednisolone in the body. For chronic therapy, synthetic steroids without mineralocorticoid activity are preferred, such as dexamethasone, betamethasone or triamcinalone. Beclo-metasone passes membranes poorly and is more active topically than when given orally. It is used as an aerosol for chronic rhinitis and asthma, and topically in severe eczema. Fludrocortisone is a synthetic halogenated derivate of cortisol that is used for its mineralocorticoid effect. 

Several systemic antibiotics that have traditionally been used in the treatment of acnevulgaris have been shown to be effective when applied topically. Currently, four antibiotics are so utilized clindamycin phosphate, erythromycin base, metronidazole, and sulfacetamide. The effectiveness of topical therapy is less than that achieved by systemic administration of the same antibiotic. Therefore, topical therapy is generally suitable only in mild to moderate cases of inflammatory acne. 

The limited penetration of topical corticosteroids can be overcome in certain clinical circumstances by the intralesional injection of relatively insoluble corticosteroids, eg, triamcinolone acetonide, triamcinolone diacetate, triamcinolone hexacetonide, and betamethasone acetate-phosphate. When these agents are injected into the lesion, measurable amounts remain in place and are gradually released for 3-4 weeks. This form of therapy is often effective for the lesions listed in Table 61-2 that are generally unresponsive to topical corticosteroids. The dosage of the triamcinolone salts should be limited to 1 mg per treatment site, ie, 0.1 mL of 10 mg/mL suspension, to decrease the incidence of local atrophy (see below). 

CLEOCIN T topical solution and CLEOCIN T topical lotion contain clindamycin phosphate at a concentration equivalent to 10 mg clindamycin per milliliter. CLEOCIN T topical gel contains clindamycin phosphate at a concentration equivalent to 10 mg clindamycin per gram. Each CLEOCIN T topical solution pledget applicator contains... 

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