Preparation and clinical application of 2% diflunisal oral ointment for painful lesions of the oral mucosa

Junko Kizu, Masao Tsuchiya, Shigekazu Watanabe, Nobuhiro Yasuno, Yoshihiro Arakawa, Hideto Saijyo, Osamu Okuda

Research output: Contribution to journalArticlepeer-review

4 Citations (Scopus)


We previously reported the development and clinical efficacy of a 2% aspirin oral ointment and 2% ethenzamide oral ointment as hospital preparations for painful lesions of the oral mucosa. This study investigated methods of preparing a more stable oral ointment with a more effective analgesic action, using diflunisal, another salicylic acid derivative, with an analgesic effect stronger than that of aspirin. A two-percent diflunisal oral ointment was prepared similarly to the aspirin ointment using plastibase and CMC-Na as the ointment base. From the results of spreadability measurement, a CMC-Na content of 20% was considered appropriate. The stability of diflunisal in 2% diflunisal oral ointment stored at 5°C, 20°C and 30°C, was determined using HPLC, and a high stability of diflunisal at room temperature for more than 100 days was confirmed. We also investigated its antinociceptive effect using the Randall-Selitto paw pressure test in rats, which showed that 2% diflunisal oral ointment was as effective as 2% aspirin oral ointment. On clinical application of 2% diflunisal oral ointment to 8 patients with painful oral mucous diseases, it was found to be significantly (p=0.014) more effective than 2% aspirin oral ointment. The results of this study demonstrated that 2% diflunisal oral ointment is a clinically useful analgesic for painful oral lesions.

Original languageEnglish
Pages (from-to)829-835
Number of pages7
JournalYakugaku Zasshi
Issue number11
Publication statusPublished - 2001
Externally publishedYes


  • Clinical application
  • Diflunisal oral ointment
  • Hospital preparation
  • Lesions of the oral mucosa

ASJC Scopus subject areas

  • Pharmacology
  • Pharmaceutical Science


Dive into the research topics of 'Preparation and clinical application of 2% diflunisal oral ointment for painful lesions of the oral mucosa'. Together they form a unique fingerprint.

Cite this