1. 2024;27;263-272Effectiveness and Safety of Flupentixol and Melitracen Tablets for the Treatment of Patients with Persistent Idiopathic Facial Pain: A Retrospective Observational Study
   Retrospective Study
   Yixuan Wang, MD, Niti Shrestha, MD, Ying Shen, MD, and Fang Luo, MD.

BACKGROUND: Flupentixol and melitracen are being investigated for their potential effectiveness in managing persistent idiopathic facial pain (PIFP), based on their mechanisms of action as dopamine receptor antagonists and noradrenaline/serotonin reuptake inhibitors, respectively. The efficacy and safety of flupentixol and melitracen (FM) tablets in treating PIFP were retrospectively analyzed at our hospital.

OBJECTIVES: The aim of this study is to determine the effectiveness and safety of FM tablets in treating PIFP.

STUDY DESIGN: Retrospective unicentric cohort design.

SETTING: An academic university hospital.

METHODS: A retrospective analysis was conducted on a cohort comprising 128 patients with a definite diagnoses of PIFP who were treated with FM tablets (flupentixol 0.5 mg and melitracen 10 mg tablet, >= 4 tablets/d) from January 2022 through May 2023 at an academic university hospital. Baseline conditions were statistically described, and Numeric Rating Scale (NRS-11) scores of pain levels before and during treatment were collected. Pain relief rates were calculated. Differences in baseline characteristics between responsive and unresponsive patients were evaluated using statistical tests. Additionally, the side effects experienced during treatment were summarized.

RESULTS: Among the included 128 patients, 105 (82.0%) patients achieved pain relief (pain NRS-11 score reduction rate >= 50%). The median treatment onset time was 3 (1-7) days. NRS-11 scores of responsive patients at week 2, week 4, week 8, and week 12 were significantly lower than the baseline NRS-11 scores (P < 0.001), regardless of their Hamilton Depression Rating Scale score. Pain duration was the only factor that related to responsiveness (Wilcoxon rank sum test, P < 0.001; logistic regression, P = 0.001). No serious side effects that could affect patients’ lives were observed during the first week of treatments.

LIMITATIONS: Due to its retrospective nature, this study is limited by its lack of a randomized control. The lack of data on nonresponders who did not achieve significant pain relief hinders assessing overall change and the placebo effects’. Patients previously treated with antidepressants were excluded, making it hard to determine if FM tablets were a better treatment for PIFP. Additionally, the small sample size in a single center may be influenced by chance variation in pain relief.

CONCLUSIONS: FM tablets showed its potential in the management of PIFP with considerable efficacy and safety. Early administration of FM tablets after a PIFP diagnosis may result in a high possibility of pain relief.

KEY WORDS: Flupentixol and melitracen, persistent idiopathic facial pain (PIFP), effectiveness, serotonin and norepinephrine reuptake inhibition (SNRIs)