Phase diagram and dissolution rate studies on solid dispersions of sulpham ethoxazole with mannitol urea

The phase diagrams of the binary systems, sulfamethoxazole-mannitol and sulfamethoxazole-urea, as obtained by hot stage microscopy and differential thermal analysis [DTA], proved the existence of an eutectic at 156C in case of the system with mannitol and an eutectic at 116C for the system containing urea with a composition of 50% [w/w] of both drug and carrier. No solid-solid solubility of the drug in the carrier was observed for sulfamethoxazole-mannitol system. A partial solid solubility was confirmed by DTA and dissolution rate studies in sulfamethoxazole-urea system. No increase occurred in the sulfamethoxazole solubility in aqueous solutions of the carriers. The dissolution rates of all fused samples were greater than those of the corresponding physical mixtures and the pure crystalline drug. The UV spectral studies revealed that no chemical interaction occurs between the solid dispersion components

Pharmacokinetic evaluation of mebeverine hydrochloride tablets

Serum mebeverine concentrations were determined in 6 subjects after administration of a single 300 mg oral dose of two mebeverine HCl commercially available tablet br and s following an overnight fast. Blood samples were collected over an 8-hour period following drug administration and the drug serum concentrations were determined by HPLC. The maximum serum mebeverine concentrations after administration of the tablet br and s A and B were 0.67 +/- 0.36 mug/ml and 0.95 +/- 0.5 mug/ml, respectively, which were attained in 3.5 hours for both products. The area under the serum mebeverine concentration-time curve was found to be 1.74 +/- 1.09 for tablets A and 2.4 +/- 1.08 mug/ml.h for tablets B. These results in a relative bioavailability of tables B of 1.38. The mean residence time, the terminal half-life, the clearance and the volume of distribution were also calculated. None of the abovementioned pharmacokinetic parameters were statistically significantly different [P >0.1]

Propylene glycol as an alcohol substitute in pharmaceutical preparations: part l- preparation of alcohol-free spirits aromatic waters and injections

Propylene glycol has been tested as a substitute for alcohol in some pharmaceutic preparations including peppermint spirit, lemon spirit, cinnamon water and diazepam injection. The preparations were evaluated by determining oil content for peppermint spirit, aldehyde content for lemon spirit and cinnamon water, and the behavior upon dilution [with saline or glucose solution] for diazepam injection. The formulae containing propylene glycol were compared with those containing alcohol and found to be suitable

Propylene glycol as an alcohol substitute in pharmaceutical preparations: part II preparation of alcohol-free elixirs

Two elixirs; namely, phenobarbitone and paracetamol elixirs, were prepared according to the official formula and a modified method in which alcohol was substituted by an equal volume of propylene glycol. The two elixirs were evaluated by determination of their drug content and their stability on storage for 2 months on the shelf. Results supported the suggestion of using propylene glycol as substitute for alcohol in the preparation of such elixirs. Furthermore, the bioavailability of phenobarbitone from the modified USP XIX formula has been evaluated by the use of Gambusia fish as a test animal. Results showed also that propylene glycol enhanced the absorption of phenobarbitone