Griseofulvin suspensions

Table 1 Photon correlation spectroscopy diameter, polydispersity index, after and before disultrafiltration, and Z-potential of griseofulvin suspension...

Wetting of the active substance can be improved by the addition of a small amount of surfactant to the aqueous phase. A surfactant reduces the surface tension between the water and the solid. A surfactant will also play a role in the character of the sediment. An example is polysorbate 80 that is processed in a griseofulvin suspension 25 mg/mL (Table 5.9). The disadvantage of surfactants in general (particularly polysorbate) is the unpleasant taste. 

Elewski BE, Caceres HW, DeLeon L, El Shimy S, Hunter JA, Korotkiy N, Rachesky IJ, Sanchez-Bal V, Todd G, Wraith L, Cai B, Tavakkol A, Bakshi R, Nyirady J, Friedlander SF. Terbinafine hydrochloride oral granules versus oral griseofulvin suspension in children with tinea capitis results of two randomized, investigator-blinded, multicenter, international, controlled trials. J Am Acad Dermatol 2008 59 41-54. 

How many milliliters of griseofulvin oral suspension containing 100 mg and 125 mg per mL should be used in preparing 100 mL of a suspension containing 12% of griseofulvin ... 

Bates TR, Carrigan PJ. Apparent absorption kinetics of micronized griseofulvin after its oral administration on single- and multiple-dose regimens to rats as a corn oil-in-water emulsion and aqueous suspension. J Pharm Sci, 1975 64 1475-1481. 

FIGURE 11.3 Mean plasma concentrations after oral administration of 50 mg/kg griseofulvin to rats. Key ( ) aqueous suspensioia Xoil suspension, ancD() o/wemulsion. (Adaptedfrom Carrigan, P.J. and Bates, T.R. 

Bates,T.R.,andJ.A. Sequeria. 1975. Bioavailability ofmicronized griseofulvin from corn oil-in-water emulsion, aqueous suspension, and commercial tablet dosage forms in humans. J Pharm Sci 64 793. 

The degree of dispersion of a lipid-based delivery system appears to have the most marked effect on the bioavailability of a co-administered drug, and this has stimulated many of the most recent articles in the literature. Clearly, by decreasing the particle size of a dispersed formulation, the surface area available for lipid digestion and drug release or transfer is enhanced. In this regard, the bioavailability of griseofulvin [32, 33], phenytoin [23], penclomedine [30], dana-zol [34], REV 5901 [35], and, more recently, ontazolast [36] has been shown to be enhanced after administration in an emulsion formulation compared with a tablet, aqueous solution, or suspension formulation. It is not clear in these cases how much more efficient the emulsion formulation would have been compared with a simple lipid solution. 

The lacquer composition contains a film-forming agent, a solvent therefore and an anti-fungal amormt of griseofulvin, which can be either in suspension or solution in the composition. It is applied to a finger or toenail and allowed to remain in contact therewith until the solvents evaporate and a thin film of griseofulvin remains. 

A soln. of Mg-iodide ether complex prepared from Mg-turnings and iodine in ether-benzene added dropwise to a stirred suspension of griseofulvin in benzene, and refluxed 3hrs. with stirring 7-chloro-4-hydroxy-6,2 -dimethoxy-6 -methyl-gris-2 -en-3,4 -dione. Y 79%. V. Arkley et al., Soc. 1962, 1260. 

Figure 7.26(a) Representative plasma concentrations of griseofulvin following oral administration of 50 mg/kg of griseofulvin suspended in lipid vehicles and water. Each curve, representing data from one animal, has a peak plasma concentration and fmax closest to the mean values for each group. For key, see Fig. 7.25. Inset correlation of the area under the plasma concentration-time curve (AUC) with the average 0 to 4 h rate of release of griseofulvin in vitro, (b) Release of griseofulvin into water from suspensions containing 5 mg drug in lipid and water. Each point represents the mean of three experiments. Key as above. From Bloedow and Hay ton [79] with permission.

From previous results, for example those of griseofulvin and dicoumarol suspensions, one might have predicted that addition of polysorbate 80 to a suspension of a poorly soluble anticonvulsant, a piperazine derivative with a solubility less than 0.1 mgml would have increased its bioavailability. But, responses in terms of the animal s protection from convulsant challenges was decreased by 0.8 % polysorbate 80 (Fig. 7.27). 

An oral suspension containing 25 mg/mL griseofulvin. Adult dose 500-1000 mg daily as a single or divided dose for 2 weeks after visible signs of infection have disappeared. 

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