Formulation of nasal analgesic sprays with diclofenac sodium, ibuprofen, paracetamol, and evaluation of in vitro toxicity.

Abstract

Intranasal analgesic sprays represent a safe, efficacious method for pain relief, with a shorter working time compared to oral painkillers. This study aimed to develop nasal sprays using commonly available over-the-counter analgesics, providing an alternative treatment option that is more convenient and potentially more effective in managing pain, particularly in pediatric patients. Three different nasal spray formulations with the contents of diclofenac sodium, ibuprofen, and paracetamol were created, and characterization studies were completed. The possible cytotoxic, genotoxic, and apoptotic effects of nasal sprays were studied on human normal skin fibroblastic cells (CCD-1079Sk) using WST cell viability test, alkaline single-cell gel electrophoresis analysis, and acridine orange/ethidium bromide staining, respectively. The formulations' physical appearance and drug content were assessed, yielding nonsignificant results (p > 0.05). All formulations were determined at pH 5.5-6.2 so that the pH values of the prepared formulations were compatible with the pH value of the nasal mucosa. Selected nasal spray formulations were stable for 90 days, and the safe doses were chosen as 0.0625, 0.375, and 1.25 mg/mL for diclofenac, ibuprofen, and paracetamol, respectively, by not showing toxicity even at 24 h. This study demonstrated that nasal sprays containing paracetamol, ibuprofen, and diclofenac sodium can be successfully formulated. These new formulations may provide alternative treatment and easier application for patients unable to swallow or refuse to take oral analgesics.