Dexamethasone phosphat

C22H29FO5 50-02-2) see Dexamethasone lert-butylacetate Dexamethasone 21-isonicotinate Dexamethasone 21 -linolate Dexamethasone phosphate Dexamethasone pivalate dexamphetamine... 

C3HjN20 96-31-1) see Theophylline dimorpholinophosphinic chloride (CgHi ClNiOgP 7264-90-6) see Dexamethasone phosphate Paramethasone Prednisolone sodium phosphate (llp,16a)-21-[(di-4-morpholinylphosphinyi)oxy]-9-fluoro-... 

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. 

Miyabo, S., T. Nakamura, S. Kuwazima, and S. Kishida. 1981. Acomparison of the bioavailability and potency of dexamethasone phosphate and sulphate in EianJ. Clin. Pharmacol20 277-282. 

More recently, polycarbophil-cysteine conjugates (thiolated polycarbophils) have been found to increase the permeation of some drugs. Hornof and Schnurch [94] found that the polycarbophil-cysteine conjugates increase the permeation of sodium fluorescein (2.2-fold) and dexamethasone phosphate (2.4-fold). The unmodified polymer... 

Hastings et al. [55] used this same in vitro technology to assess the enhancement delivery of dexamethasone using the Visulex iontophoretic system. The Visulex applicator and a freshly excised rabbit sclera were positioned between two halves of a side-by-side diffusion cell with the conjunctival side of the sclera facing the applicator (Figure 26.10). The donor drug solution (1 mg of dexamethasone phosphate) was present in the applicator, and diluted vitreous humor was modeled in the receptor cell. One milliampere direct current was applied for 60 min, and samples were collected during different treatment periods. It was demonstrated that the Visulex system produced a twofold increase in the amount of dexamethasone phosphate delivered after 60 min, compared with a standard iontophoretic administration (without the Visulex applicator). 

Steroids are poorly investigated for the transcorneal route despite the fact that dexametha-sone seems to have a much higher corneal penetration than the positively charged antibiotics after corneal iontophoresis. Eljarrat-Binstock et al. [56] used dexamethasone phosphate-loaded hydrogels for the iontophoretic delivery, applying only 5.1 mA/cm2 current for 1 and 4 min. Enormous amounts of dexamethasone (3077.5 and 1363.7 pg/g) were detected... 

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