Real-Time Chemical, Microbiological, and Physical Stability of Extemporaneously Compounded Amiloride Nasal Spray Over 90 Days at Refrigerated and Room Temperatures.

Abstract

Amiloride is a commonly known FDA-approved diuretic used to treat hypertension and congestive heart failure. In more recent years, it has been postulated that it might also serve as an anxiolytic agent due to its agonistic effects on acid-sensing ion channels (ASIC). An intranasal administration of an extemporaneously compounded amiloride would allow for easy and rapid access to the site of action to alleviate symptoms of anxiety and other related disorders. However, compounded patient-preparations do not have the chemical stability or pre-formulation characterization that typical manufactured dosage forms have. The purpose of this study was to assess the real-time chemical, microbiological, and physical stability of extemporaneously compounded amiloride nasal spray over the course of 90 days. This was accomplished via a validated, high-performance liquid chromatography (HPLC) method at designated and appropriate time points to reveal that amiloride remained highly chemically stable over 50 days at 4 and 20 degrees Celsius and retained sufficient stability after 90 days from initial compounding. Additionally, the physical stability of the solution when combined with the preservative benzyl alcohol was confirmed via visual inspection, pH monitoring, and measuring of turbidity.