In the majority of cases, the therapeutic dose of a drug is relatively small and therefore the API has to be mixed with suitable excipients to achieve a desired fill volume that allows for compression of the powder mixture into a suitably sized tablet. Therefore, these studies do result in incomplete process and product understanding. However, such empirical dissolution models have a number of inherent drawbacks, including that i) the elucidation of the underlying mass transport mechanisms is not possible ii) not a single characteristic parameter of the dosage form is related to the intrinsic dissolution rate of the drug and iii) the generality of such empirical models is limited. It is common practice to estimate the in-vivo performance of a drug product on its in-vitro drug release profile by establishing empirical in-vivo in-vitro correlations during the pharmaceutical product development. Such modification of the drug release can be achieved either by embedding the API in a polymer matrix that dissolves or swells at a slower rate than the drug or by means of a suitable polymer coating that acts as a mass transfer limiting barrier. In contrast, in modified - release tablets the API release may be designed to be gradual in order to achieve slow and sustained dissolution in, or selective absorption across, the gastrointestinal (GI) tract, and/or resulting in a delayed onset time. for analgesics or to enable enhanced bioavailability of a poorly soluble drug substance. Such formulations are particularly important where a rapid onset of action is desired, e.g. Such a fast disintegration is even more important for orally dispersible tablets, which are designed to disintegrate in the mouth in less than a minutes before swallowing. Immediate-release tablets are designed to fully disintegrate and dissolve upon exposure to physiological fluids within a short period of time (2.5 to 10 min). By choosing suitable chemical and physical properties tablets can be formulated to either release their API immediately following oral administration (immediate-release tablets) or to modify the drug release profile with the aim to achieve improved therapeutic efficacy, reduced toxicity, and improved patient compliance and convenience (modified release tablets). Within this group disintegrating tablets constitute by far the bulk of pharmaceutical products. Solid dosage forms, such as tablets and capsules, still represent the most widespread technology to orally administer active pharmaceutical ingredients (API) to the patient. This review further summarises mathematical models used to simulate disintegration phenomena and to predict drug release kinetics.
Its mechanisms and the factors impacting disintegration are discussed and methods used to study the disintegration in-situ are presented. The disintegration process is specifically critical for immediate-release dosage forms. The performance of a drug is primarily influenced by the disintegration and dissolution behaviour of the powder compact.
These complex porous systems undergo different mechanisms when they come in contact with physiological fluids. Excipients are added to a formulation in order to achieve the desired fill weight of a dosage form, to improve the processability or to affect the drug release behaviour in the body. Tablets are typically powder compacts consisting of several different excipients in addition to the API.
Pharmaceutical solid dosage forms (tablets or capsules) are the predominant form to administer active pharmaceutical ingredients (APIs) to the patient.
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