Topical release

Inhibitors of histamine release One of the effects of the so-called mast cell stabilizers cromoglycate (cromolyn) and nedocromil is to decrease the release of histamine from mast cells (p. 72, 326). Both agents are applied topically. Release of mast cell mediators can also be inhibited by some Hi antihistamines, e.g., oxatomide and ketotifen, which are used systemically. 

Topical release and permeation studies of propranolol hydrochloride from hydrophilic polymeric matrices... 

To investigate the pharmacokinetics (PK) of an XYZ1234 formulation (200 mg) following topical release in the proximal small bowel, distal small bowel and colon via the Enterion capsule in healthy subjects and to compare to the PKof an XYZ1234 immediate release reference formulation (200 mg). 

Dermal drug administration is yet another pharmaceutical application of chitosan. Topical all-frans-retinoic acid (ATRA) is an effective treatment for serious malignant melanoma. However, this topical retinoid incites skin irritation in the wide majority of patients, rendering it an ineffective treat-ment. As evidenced by the research of Cattaneo and Demierre, chitosan gels avail themselves to sustained, topical release of ATRA. These studies showed that manipulation of the viscosity or chitosan concentration of the gel enabled control of percutaneous penetration of the drug in mouse skin samples. In addition, their clinical trials on healthy hiunan subjects indicated minimal erythema occurrence from application of 0.1% ATRA in 1% and 3% chitosan gel. 

In addition, for encapsulated material to be released in a controlled manner, mechanical properties of microcapsules are of considerable significance. This particularly refers to microcapsules embedded in textile structures intended for the topical release of an active agent, when they demand sufficient stability to withstand wear and tear (Neubauer et al., 2014). 

B. Eckenhoff, in "Controlled and Topical Release Session of the AICHE Meeting", June 10, 1980, Philadelphia, PA... 

Sorbitan sesquioleate emulsions of petrolatum and wax are used as ointment vehicles in skin treatment. In topical appHcations, the inclusion of both sorbitan fatty esters and their poly(oxyethylene) derivatives modifies the rate of release and promotes the absorption of antibiotics, antiseptics, local anesthetics, vasoconstrictors, and other medications from suppositories, ointments, and lotions. Poly(oxyethylene(20)) sorbitan monooleate, also known as Polysorbate 80 (USP 23), has been used to promote absorption of ingested fats from the intestine (245). 

Ivermectin is widely used as an endectocide for catde as an injectable, oral, topical, or slow release bolus for sheep as an injectable or oral formulation for swine as an injectable for horses as a paste or drench and for goats as an injectable or oral formulation. Ivermectin has recently been introduced for heartworm prophylaxis in dogs and it is being studied for use with cats, many other mammals, birds, fish, and reptiles. 

The topic of flare gas measurement is treated below. If necessary, continuously vented surplus low pressure steam can be used for smoke control at low flaring rates, with high pressure steam cutting in through a flare ratio controller designed to handle large releases. 

The Center for Chemical Process Safety s projects fall into a number of general topic areas that comprise a comprehensive program. These topic areas include identification of hazards and analysis of risks, prevention and mitigation of the hazards identified, and better definition of areas affected by a release of hazardous materials. This book is the latest in the series dealing with hazard identification and risk analysis. 

In 1985, Uie Cimadian Chemical Producers Association (CCPA) released a pampWet entitled, "Essential Components of Safety Assessment Systems . Modifications to process or plant was one of the topics discussed in Uiis pamplilet. CCPA recommended a 12 element program (listed below) to formally e.xamine and approve process conditions whellier permanent or temporary prior to implementation. 

This section focuses on industrial accidents tliat are not plant related and revievs ing accidents tliat occur during tlie transport and storage of hazardous substances. Frequently, such accidents result in fires, explosions, and toxic releases. This topic will be discussed in tlie next cliapter. 

In the process of identifying chemical health hazards, tlie near term and long tenn fate of tlie hazard should be incorporated into tlie analysis. Near-term concerns relate primarily to tlie release of the chemical into the enviromnent. This leads to the general subject area of e.xposure assessment, including routes of e.xposure - a topic that is treated in e.xtensive detail in Cliapter 12. However, tlie fate of the chemical (hazard) following tlie point of human entry is another consideration when attempting to identify health hazards. An overview of tliis topic is presented here... 

Of these, noxythiolin (N-hydroxy-Af-methylthiourea) has the greatest pharmaceutical use as an antimicrobial agent. The compound is supplied as a dry powder and on aqueous reconstitution slowly releases formaldehyde and iV-mefhylthiourea. Antimicrobial activity is considered to be due to both the noxythiolin molecule and the released formaldehyde. Noxythiolin is used both topically and in accessible body cavities as an irrigation solution and in the treatment of peritonitis. The compound has extensive antibacterial and antifungal properties. 

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