Pentamidine solution

Reconstitution-The contents of 1 vial must be dissolved in 6 mL Sterile Water for Injection, LISP. It is important to use only sterile water saline solution will cause the drug to precipitate. Place the entire reconstituted contents of the vial into the Respirgard II nebulizer reservoir for administration. Do not mix the pentamidine solution with any other drugs. 

Patients suffering from cystic fibrosis often use various aerosolized drugs. To reduce the viscosity of the mucus in the airways, recombinant human deoxyribonuclease is used. This enzyme is the first recombinant protein that has been developed for specific delivery to the lungs via the airways. It has a local action on the mucus in the airways and its absorption is minimal. Another drug that decreases the viscosity of the mucus is acetylcysteine. Aerosolized antibiotics are a further group of therapeutics that is widely used by cystic fibrosis patients. Solutions of antibiotics like tobramycin or colistin are used in nebulizers to prevent exacerbation of the disease. Pentamidine has been used for the prophylaxis of Pneumocystis pneumonia in patients infected with HIV virus, while chronic rejection of lung transplants provided a reason to develop an aerosol formulation of cyclosporine A. 

Pentamidine Pentamidine, 4-4 -(pentamethylendioxy)dibenzamidine (37.4.2), is made by reacting 4-hydroxybenzonitrile with 1,5-dibromopentane in the presence of sodium hydroxide to make l,5-few-(4-cyanophenoxy)pentane (37.4.1). Subsequent reaction of this with an ethanol solution of hydrogen chloride with the intermediate formation of an iminoester, and then with an ethanol solntion of ammonia gives the desired pentamidine [55-57]. 

Pentamidine isethionate solution is incompatible and precipitates immediately with cephalosporin and cephalomycin injections when admixed with 5% glucose infusions.16... 

Foscamet sodium should not be mixed with any intravenous infusion drug, since it interacts with glucose- and calcium-containing solutions and sodium, ganciclovir, certain antibacterials, amphotericin, pentamidine isethionate, and trimetrexate.18 Care must be taken to avoid inhalation and exposure of the skin to zalcitabine powder. 

Both the inhalant (aerosol) and parenteral dosage forms of pentamidine iselhionale arc sterile lyophilized powders that must be made up as sterile aqueous solutions prior to use. Sterile water fur injection must be used to reconstitute the aerosol, to avoid precipitation of the pentamidine salt. Adverse reactions to the drug ate common. These include cough and bmnehospasm (inhalation) and hypertension and hypoglycemia (injection). 

Williams, N. A., and D. L. Schwinke. 1994. Low temperature properties of lyophilized solutions and their influence on lyophilization cycle design Pentamidine isothionate./. Pharm. Sci. Technol. 48 135-139. 

Pentamidine isethionate is marketed for injection (pentam 300) or for use as an aerosol (NEBU-pent). One milligram of pentamidine base is equivalent to 1.74 mg of the pentamidine isethionate. The isethionate salt is highly water soluble. Solutions should be used promptly because pentamidine is unstable in solution. 

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