Dosage form oral drugs

Qiang, D., Gunn, J. A., Schultz, L., Li, J. Evaluation of the impact of sodium lauryl sulphate source variability on solid oral dosage form development. Drug Dev. Ind. Pharm., 36(12), 2010, 1486-1496. 

Modified Release Dosage Forms Dosage forms whose drug-release characteristics of time course and/or location are chosen to accomplish therapeutic or convenience objectives not offered by conventional dosage forms such as a solution or an immediate release dosage form. Modified release solid oral dosage forms include both delayed and extended release drug products. 

Zhang GZ, Law D, Schmitt EA, Qiu Y. 2004. Phase transformation considerations during process development and manufacture of solid oral dosage forms. Adv. Drug Deliv. Rev. 56 371-390. 

A suspension is often chosen as pharmaceutical dosage form for drugs insoluble in water and aqueous fluids at the dosage required for administration and when attempts to solubilize the drug would compromise stability and safety. For oral administration, the taste of a bitter or unpleasant drug can often be masked by choosing an insoluble form of the active drug. 

For drugs with short half-lives (30 min to 3 h) and a relatively narrow margin of safety, the use of an inconveniently short dosage interval (< 6 h) would be required to maintain plasma concentrations within the therapeutic range. This situation applies to carbamazepine and valproic acid (anticonvulsants), which are commercially available as conventional oral dosage forms. For drugs with a... 

Of the numerous phenothiazines possessing piperazinylpropyl side-chains, fluphena-zine has been the most studied in terms of its pharmacokinetic properties. The apparent reason for the interest in fluphenazine is that it is available in both oral and depot injectable dosage forms. Oral fluphenazine experiences extensive first pass metabolism (419-422) to form numerous metabolites, all of which are less active than the parent drug (410, 420-426). A distribution study of orally administered fluphenazine using radioimmunoassay established that brain concentrations of fluphenazine exceeded plasma concentrations by 10 to 27 times (420). The inactive sulfoxide was the major metabolite found in brain, while brain levels of 7-hydroxy-fluphenazine and fluphenazine-N-oxide were very low (420). It was concluded that metabolites do not contribute to the pharmacology of fluphenazine and that only the plasma level of the parent drug needs be monitored for correlation to therapeutic response. 

Molecular Pharmaceutics, Vol. 5, No. 6, (October 2008), pp. 905-920, ISSN 1521-0111 Zhang, G.G. Law, D. Schmitt, E.A. Qiu, Y. (2004). Phase Transformation Considerations During Process Development and Manufacture of Solid Oral Dosage Forms. Advanced Drug Delivery Reviews, Vol. 56, No. 3, (February 2004), pp. 371-390, ISSN0169409X... 

Reppas, C., Shah, V. P. Dissolution testing as a prognostic tool for oral drug absorption immediate release dosage forms. Pharm. Res. 1998, 15, 11-22. 

The rationale of the dosage form design (e.g., if a drug is rapidly destroyed in solution at a pH of 2 or below, the design of an oral product must enable the drug to get through the stomach without substantial dissolution)... 

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