Excipient antimicrobial

Uses Excipient, antimicrobial in pharmaceuticals, veterinary medicine antibacterial drug... 

Single-dose preparations intended for use in eye surgery do not contain excipient ingredients, in order to avoid tissue irritation. However, multiple-dose containers may require antioxidants (qv), antimicrobial preservatives, or buffers to maintain stabiHty and stefiHty. Such solutions are packaged in polyethylene flexible dropper units called droptainers or in glass dropper botdes. 

This aromatic alcohol has been an effective preservative and still is used in several ophthalmic products. Over the years it has proved to be a relatively safe preservative for ophthalmic products [138] and has produced minimal effects in various tests [99,136,139]. In addition to its relatively slower rate of activity, it imposes a number of limitations on the formulation and packaging. It possesses adequate stability when stored at room temperature in an acidic solution, usually about pH 5 or below. If autoclaved for 20-30 minutes at a pH of 5, it will decompose about 30%. The hydrolytic decomposition of chlorobutanol produces hydrochloric acid (HC1), resulting in a decreasing pH as a function of time. As a result, the hydrolysis rate also decreases. Chlorobutanol is generally used at a concentration of 0.5%. Its maximum water solubility is only about 0.7% at room temperature, which may be lowered by active or excipients, and is slow to dissolve. Heat can be used to increase dissolution rate but will also cause some decomposition and loss from sublimation. Concentrations as low as 0.125% have shown antimicrobial activity under the proper conditions. 

The choice of the excipients and their concentration, including their function (e.g., antimicrobial preservatives, antioxidants. ..). In the case of antimicrobial preservatives, data are expected on the preservative efficacy in products on storage, including after reconstitution or dilution and during the period of use. 

With the exception of antimicrobial preservatives and antioxidants (see below) and coloring matter (for which an identity test should be available), it is not normally necessary to test for the presence of excipients in finished products. 

Where antioxidants or antimicrobial preservatives are used, the finished product release specification will need to include identification tests and assays for these two types of excipient. The shelf life specification should also include a specification for assay for antimicrobial preservatives. Stability data will be required for both antioxidants and antimicrobial preservatives in the finished product, and in addition the preservative efficacy of the formulated product should be examined over its shelf life and by means of appropriate in-use stability tests. Preservative efficacy data should also be presented at the lower limit of the preservative assay. 

Mouthwashes are aqueous concentrated solutions containing one or more active ingredients and excipients. They are used by swishing the liquid in the oral cavity. Approximately 15-30 ml. of mouthwash are used for single mouthful of rinse for about a minute. Mouthwashes can be used for therapeutic and cosmetic purpose. Therapeutic mouthwashes are used to reduce plaque, dental caries, gingivitis and stomatitis while cosmetic mouthwashes are used to reduce bad breath and it contains used antimicrobial and/or flavoring agent. Mouthwashes other than used for cosmetic purpose, should only be used under the direction of physician/dentist since it contains certain medicines. 

The inactive ingredient is used at a level no higher than reasonably required to achieve its physical or technical function. For example, an antimicrobial excipient ingredient could only be used at a level consistent with preservation of the finished product (not at therapeutic levels), and a sunscreen ingredient could only be used at levels that protected the product from breaking down if the top of the jar was left open, not for protecting the user. 

Note for Guidance on Excipients, Antioxidants, and Antimicrobial Preservatives in the Dossier for Marketing Authorization of a Medicinal Product. The European Agency for the Evaluation of Medicinal Products, 2003. 

Preservatives In addition to those processing controls mentioned above (Section 3.1.4.3), the sterility of a product may be maintained through the addition of antimicrobial preservatives. Preservation against microbial growth is an important aspect of multidose parenteral preparations as well as other formulations that require preservatives to minimize the risk of patient infection upon administration, such as infusion products [52], Aqueous liquid products are prone to microbial contamination because water in combination with excipients derived from natural sources (e.g., polypeptides, carbohydrates) and proteinaceous active ingredients may serve as excellent media for the growth [57], The major criteria for the selection of an appropriate preservative include efficiency against a wide spectrum of micro-... 

Parenteral products contain excipients such as buffers, solvents, non-aqueous solvents, antimicrobial... 

Excipients such as buffers, antimicrobials, antioxidants and chelating agents may be required for optimal drug stability in IDDS formulations. Several unique criteria when selecting excipients must be considered. 

In ophthalmic preparations, benzalkonium chloride is one of the most widely used preservatives, at a concentration of 0.01-0.02% w/v. Often it is used in combination with other preservatives or excipients, particularly 0.1% w/v disodium edetate, to enhance its antimicrobial activity against strains of Pseudomonas. 

Chlorhexidine and its salts are widely used, primarily as topical disinfectants. As excipients, chlorhexidine salts are mainly used as antimicrobial preservatives in ophthalmic formulations. 

Chlorocresol is used as an antimicrobial preservative in cosmetics and pharmaceutical formulations. It is generally used in concentrations up to 0.2% in a variety of preparations except those intended for oral administration or that contact mucous membrane. Chlorocresol is effective against bacteria, spores, molds, and yeasts it is most active in acidic media. Preservative efficacy may be reduced in the presence of some other excipients, particularly nonionic surfactants, see Sections 10 and 12. 

As a pharmaceutical excipient, chloroxylenol is commonly used in low concentrations as an antimicrobial preservative in topical formulations such as creams and ointments. Chloroxylenol is also used in a number of cosmetic formulations. 

As an excipient, sodium propionate is used in oral pharmaceutical formulations as an antimicrobial preservative. Eike propionic acid, sodium propionate and other propionic acid salts are fungistatic and bacteriostatic against a number of Gram-positive cocci. Propionates are more active against molds than is sodium benzoate, but have essentially no activity against yeasts see Section 10. 

In pharmaceutical analysis, the majority of matrix components (excipients) are present to improve manufacturing characteristics like bulk powder flow, tablet hardness, or to enhance tablet disintegration.12 Other excipients are present in a formulation to preserve the active pharmaceutical ingredient13 (antioxidant, for example) or to act as an antimicrobial agent14 (methylparaben, for example). Still other excipients may be present to increase the palatability of the formulation15 (flavors, for example). 

Several antimicrobial agents must be screened for compatibility with the proteins and the excipients of the formulation. Table 15.4 summarizes the various characteristics of preservatives. 

The multidose formulation will be tested to determine its efficacy according to the Antimicrobial Effectiveness Test required by the USP.39 If the results support the USP requirements, international requirements must then be met. International markets require different preservatives, different concentrations, and different excipients of the formulation. In addition, the period required for the inhibition and/or killing of the challenge microorganisms may be different. International regulatory requirements for compliance should be well researched and understood by the scientific and the management staff. 

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