Bioavailability,or the extent to which the therapeutic constituent of a pharmaceutical dosage form intended for oral or topical use is available for absorption,is influenced by a variety of factors.Among the inherent factors known to affect absorption are the method of manufacture or method of compounding;the particle size and crystal form or polymorph of the drug substance;and the diluents and excipients used in formulating the dosage form,including fillers,binders,disintegrating agents,lubricants,coatings,solvents,suspending agents,and dyes.Lubricants and coatings are foremost among these.The maintenance of a demonstrably high degree of bioavailability requires particular attention to all aspects of production and quality control that may affect the nature of the finished dosage form.