Pharmaceutical Considerations Research Articles

Addition of drugs to infusion fluids: pharmaceutical considerations on preparation and use.

In most hospitals, the addition of drugs to infusion fluids is carried out by nurses. The preparation involves certain hazards both microbiologically and pharmaceutically. Incompatibilities between drug and fluid or between drugs may result in admixtures which have reduced therapeutic activity or which are even hazardous to the patient. The all-in-one total parenteral nutrition mixtures represent a new way of administering nutrition and has achieved increased popularity both for in- and outpatients. During preparation, which takes place in the pharmacy, several precautions have to be taken to assure a product with acceptable stability. Some of the important incompatibilities are mentioned.

Pharmaceutical considerations of transdermal nitroglycerin delivery: The various approaches

When formulated as a sublingual or an oral sustained-release dosage form, nitroglycerin has certain shortcomings, i.e., decreased duration of antianginal action and extensive hepatic first-pass elimination, which limit its efficacy. The finding that administration of nitroglycerin in the form of topical ointment decreases the extent of hepatic first-pass elimination and increases the duration of therapeutic activity has pointed the way to the possibility of developing a more effective transdermal drug delivery device. Three such devices are the Nitrodisc, Nitro-Dur, and Transderm-Nitro systems. All three systems generate effective plasma drug levels within 30 minutes and maintain steady-state drug plasma levels as follows: the 16 cm 2 Nitrodisc at 280.6 ± 18.7 pg/ml for 32 hours; the 20 cm 2 Nitro-Dur at 201.4 ± 60.7 pg/ml for 24 hours; and the 20 cm 2 Transderm-Nitro system at 209.8 ± 22.8 pg/ml for 24 hours. In vitro studies show that the drug penetrates the skin with zero-order kinetics in all three systems, the rate for Nitrodisc being 20% greater than that of the other systems. When the daily nitroglycerin dose is calculated in terms of skin permeation rate and the device's surface area, the three transdermal systems become clinically interchangeable.

Pharmaceutical considerations of nitroglycerin.

During the past few years, there have been rapid changes in the pharmaceutical uses of nitroglycerin. New dosage forms and new delivery systems have become available, which have resulted in potential confusion to all concerned with the proper use of these systems. The goal of this review is to prevent confusion and to bring all the relevant information together. The various analytical techniques available for quality control of the dosage forms and for the study of the pharmacokinetics are reviewed, with the intent of enabling the reader to identify pertinent references rapidly. The interaction of nitroglycerin with packaging and plastic delivery devices is also reviewed so that the reader can make informed choices. Finally, the clinical pharmacy and pharmacokinetics are reviewed so as to bring the reader up to date in that area. After reading this article, the areas of nitroglycerin research that still need to be explored should be apparent.