Semisolids form evaluation

Concern for the physical and chemical integrity of topical systems is no different than for other dosage forms. However, there are some unique and germane dimensions to stability associated with semisolid systems. A short list of some of the factors to be evaluated for semisolids is given in Table 12. All factors must be acceptable initially (within prescribed specifications), and all must remain so over the stated lifetime for the product (the product s shelf life). 

Use of these semisolid and solid approaches can potentially alleviate the chemical stability problems sometimes observed for liquid-Llled formulations, and may eventually offer the possibility of development of a tablet dosage form using conventional equipment. Liquid lipid-based formulations, however, generally afford the greatest enhancement of bioavailability for water-insoluble drugs, as well as affording more rapid development for First-in-Human studies. Any decisions on the best formulation route would have to be evaluated on a case-by-case basis. 

APV (1981) International Association for Pharmaceutical Technology Praxis der Validierung (Validation in Practice), Symposium (1981-1982, Gelsenkirchen) [6] Terminology, sterile, semisolid, and solid dosage forms in development and production, analytical methods and stability evaluation, packaging development and packaging validation transfer, cost-effectiveness... 

The formulation, evaluation, and regulatory feature of the three most commonly used semisolid dosage forms, ointments, creams, and gels, are described in this chapter. 

Seta, Y. Higuchi, E. Otsuka, T. Kawahara, Y. Nishimura, K. Okada, R. Koike, H. Preparation and pharmacological evaluation of captopril sustained-release dosage forms using oily semisolid matrix. Int. J. Pharm. 1988, 41 (3), 255-262. 

Guidance for Industry Nonsterile Semisolid Dosage Forms Scale-Up and Postapproval Changes Chemistry, Manufacturing, and Controls In Vitro Release Testing and In Vivo Bioequivalence Documentation. U.S. Department of Health and Human Services Food and Drug Administration Center for Drug Evaluation and Research (CDER), May 1997. 

Non-Sterile Semisolid Dosage Forms Scale-Up and Post Approval Changes Center for Drug Evaluation and Research (CDER) May 1997 FDA Guidance for Industry. 

Shah, V.P. FDA guidance for industry document. In Non-sterile Semisolid Dosage Forms Center for Drug Evaluation and Research Rockville, MD, 1997 1-40. 

In physical form, oleoresins range from thin to viscous fluids, from semisolids to waxy or sticky pastes. Samples should be well mixed to ensure uniformity before testing. Initially, the sample should be evaluated for appearance (often characteristic), odor and flavor after dilution in a suitable medium. 

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