Propellant Free Pressurized Spray System of Etodolac to Manage Acute Pain Conditions: In Vitro and In Vivo Evaluation

AAPS PharmSciTech. 2024 May 14;25(5):112. doi: 10.1208/s12249-024-02807-9.

Abstract

This study aimed to develop a propellant-free topical spray formulation of Etodolac (BCS-II), a potent NSAID, which could be beneficial in the medical field for the effective treatment of pain and inflammation conditions. The developed novel propellant-free spray formulation is user-friendly, cost-effective, propellant-free, eco-friendly, enhances the penetration of Etodolac through the skin, and has a quick onset of action. Various formulations were developed by adjusting the concentrations of different components, including lecithin, buffering agents, film-forming agents, plasticizers, and permeation enhancers. The prepared propellant-free spray formulations were then extensively characterized and evaluated through various in vitro, ex vivo, and in vivo parameters. The optimized formulation exhibits an average shot weight of 0.24 ± 0.30 ml and an average drug content or content uniformity of 87.3 ± 1.01% per spray. Additionally, the optimized formulation exhibits an evaporation time of 3 ± 0.24 min. The skin permeation study demonstrated that the permeability coefficients of the optimized spray formulation were 21.42 cm/h for rat skin, 13.64 cm/h for mice skin, and 18.97 cm/h for the Strat-M membrane. When assessing its potential for drug deposition using rat skin, mice skin, and the Strat-M membrane, the enhancement ratios for the optimized formulation were 1.88, 2.46, and 1.92, respectively against pure drug solution. The findings from our study suggest that the propellant-free Etodolac spray is a reliable and safe topical formulation. It demonstrates enhanced skin deposition, and improved effectiveness, and is free from any skin irritation concerns.

Keywords: analgesic; anti-inflammatory; enhanced permeation; etodolac; propellant-free spray.

MeSH terms

  • Acute Pain / drug therapy
  • Administration, Cutaneous*
  • Animals
  • Anti-Inflammatory Agents, Non-Steroidal / administration & dosage
  • Anti-Inflammatory Agents, Non-Steroidal / pharmacokinetics
  • Chemistry, Pharmaceutical / methods
  • Drug Compounding / methods
  • Etodolac* / administration & dosage
  • Etodolac* / chemistry
  • Etodolac* / pharmacokinetics
  • Male
  • Mice
  • Permeability
  • Rats
  • Rats, Sprague-Dawley
  • Skin Absorption* / physiology
  • Skin* / drug effects
  • Skin* / metabolism