established that bactericidal killing is rapid, intensive and increases proportionately to the concentration. In the presence of high concentration of the drug, the killing is complete and almost instantaneous. In some drugs rapid and complete absorption and high systemic concentration are important to elicit the desired therapeutic effect.
Extremely unpleasant tasting active ingredients may require a higher concentration of polymer to obtain the desirable level of taste masking. However this may delay the release of the active ingredient from the formulation. For certain polymers like polymethacrylates the recommended safe daily dose is 2 mg/kg of body weight (Rohm Pharma GmbH. Technical Literature, Eudragit 1990 and Hand book of Pharmaceutical Excipients published by American Pharmaceutical Association & The Pharmaceutical Society of Great Britain) there by restricting the use of highersystems cannot be formulated in the liquid dosage forms since there is a possibility of release of the active in the reconstitution media and also the recrystallization of the active ingredient in contact with the aqueous media.
Patent Application WO 00/71098 discloses the method of preparing a pharmaceutical composition comprising of amorphous paroxetine and maintain it in the amorphous form by the use of a cosolvent polyethylene glycol and a complexing agent crosspovidone. In the above invention use of the cosolvent is essential to maintain the amorphous form of paroxetine and its absence causes the recrystallization of the active ingredient even in the presence of complexing agent. Additives like polyethylene glycol, as a cosolvent will not be useful in pharmaceutical preparation where leaching of drug in aqueous media is