Stability of extemporaneously compounded spironolactone suspensions

Area of Science:

• Pharmaceutical Sciences
• Drug Stability
• Formulation Development

Background:

• Spironolactone is a widely prescribed medication.
• Assessing the stability of extemporaneously prepared liquid formulations is crucial for patient safety and therapeutic efficacy.
• Liquid formulations offer an alternative for patients with difficulty swallowing tablets.

Purpose of the Study:

• To evaluate the short-term stability of spironolactone in liquid suspensions.
• To determine the optimal storage conditions and duration for extemporaneously prepared spironolactone formulations.
• To assess the impact of temperature and light on spironolactone degradation in a cherry syrup base.

Main Methods:

• Spironolactone suspensions were prepared from tablets at concentrations of 2.5, 5.0, and 10.0 mg/mL using Purified Water, USP, and Cherry Syrup, NF.
• Stability-indicating high-performance liquid chromatography (HPLC) was employed to measure drug concentrations.
• Samples were stored at 5°C, ambient room temperature (20-24°C), and 30°C for two and four weeks.

Main Results:

• No significant spironolactone loss was observed in cherry syrup formulations stored for two weeks under tested conditions.
• Degradation remained below 5% for samples stored for four weeks.
• Microbial counts, color, and odor remained within acceptable limits throughout the study period.

Conclusions:

• Extemporaneously prepared spironolactone suspensions in Cherry Syrup, NF, demonstrate good short-term stability for up to four weeks.
• These findings support the use of these liquid formulations for short-term patient use.
• Further studies may be warranted to assess long-term stability and compatibility with other excipients.