Stability Of Sildenafil Citrate Oral Suspension With Syrspend^® Sf

Aim: Sildenafil citrate is a drug used to treat erectile dysfunction (ED) and pulmonary arterial hypertension (PAH). As for both clinical applications, the only available dosage form is tablets; there is a clear need for a safe oral liquid, especially for children. The objective of this study was to determine the stability of sildenafil citrate in SyrSpend® SF PH4, a suspending agent containing neither sorbitol nor alcohol.

Material/Methods: The studied sample was compounded into a 2.5-mg/mL suspension and stored in low-actinic plastic bottles at temperatures between 2 and 8°C and at room temperature conditions. Six samples were assayed at each time point out to 92 days by a high-performance liquid chromatography (HPLC) method. The method was validated for its specificity through forceddegradation studies.

Results: The samples remained within 90–110% of the initial concentration throughout the course of the study. Conclusions: On the basis of the data collected, the beyond-use date of this product is at least 92 days when protected from light at both refrigerated and room temperature storage conditions.