Solid dosage forms modified release

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. 

The contents of this chapter are applicable to both product development and QC laboratories. Although the principles discussed in the chapter are presented in the context of immediate-release solid dosage forms, they can be applied to modified-release and suspension dosage forms if it is within the capability of the... 

Table 4 SUP AC MR (Modified Release Oral Solid Dosage Forms)... 

In order to achieve therapeutic effect, a drug needs to reach the right place in the body at the right time. For some drugs, this may be achieved by simple solutions or solid dosage forms with an instant drug release while, for others, one has to modify... 

A medication available only as a solid dosage form, may be prepared as an extemporaneous liquid (e.g., suspension) or it may be modified for oral use, for example, by crushing. As mentioned previously, a sustained-release product should not be crushed or chewed. For a solid, non-sustained-release medication, the product can be crushed and mixed with a small amount of food just prior to administration. Examples of foods that may be used for mixing include applesauce, yogurt, or instant pudding, but the medication should not be added to an entire dish of food or to infant formula, because the infant or child may not eat/drink the entire portion and thus not receive the total amount of medication. 

Cetyl alcohol is widely used in cosmetics and pharmaceutical formulations such as suppositories, modified-release solid dosage forms, emulsions, lotions, creams, and ointments. 

Experimentally, potassium chloride is frequently used as a model drug in the development of new solid-dosage forms, particularly for sustained-release or modified-release products. 

Addition or deletion of a code imprint by embossing, debossing, or engraving on a solid dosage-form drug product other than a modified-release dosage form... 

An alternative to any type of solution is to keep the drug substance in a particulate solid state. This is the normal formulation approach taken for solid dosage forms for oral administration. As long as the rate of dissolution is sufficient to release and dissolve the drug dose in the gastric and intestinal fluids, no problems will arise. The rate of dissolution / of a solid depends mainly on two parameters, namely the solubility C in the aqueous phase and on the specific surface area A of the drug dose that is exposed to the solvent according to the Nemst-Brurmer modified Noyes-Whitney equation ... 

If the active substance is not available as raw material it may be processed from oral solid dosage forms by adapting those. Not all solid dosage forms however are tit for such an operation. Tablets with a gastro-resistant coating or modified-release tablets should not be crushed unless the product information confirms its suitability, see further Sect. 4.10.7. 

Many of the published reports in the literature on the use of pH modifiers in solid dosage forms are for controlling the drug release from modified-release dosage forms, such as matrix tablets and coated tablets and beads (Gohel et al. 2003 Kranz et al. 1969 Naonori et al. 1991 Siepe et al. 2006 Streubel et al. 2000 Tatavarti and Hoag 2006 Thoma and Zimmer 1990). The pH modifiers have also been used to prevent disproportion of salts in tablets (Zannou et al. 2007). The use of pH modifiers in solid dispersion to enhance dissolution rate of drugs is, however, rather limited. 

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