Changing landscape of lignocaine spray clinical trials: An analysis of the Clinical Trials Registry of India

INTRODUCTION Lignocaine spray is widely used for rapid topical anesthesia during airway manipulation, endoscopy, venepuncture, dental procedures, and minor gynecological interventions.1 It reduces postintubation airway events, sore throat, and extubation-related cough2,3 and provides effective analgesia for dental and mucosal procedures across age groups.4,5 Despite its favorable safety profile and broad clinical acceptance, considerable variation exists in concentration, dosing, and timing, with limited uniform guidance.4 Global topical anesthesia research shows methodological heterogeneity, and consolidated India-specific evidence remains sparse.6-8 This study analyzes Clinical Trials Registry of India (CTRI)-registered trials to understand research trends and evidence gaps over the past 17 years. MATERIALS AND METHODS A retrospective review of all trials registered in the CTRI from July 2007 to December 2025 was conducted using the keyword “lignocaine spray.” Studies were included if lignocaine spray was used as an intervention, comparator, or procedural adjunct. Extracted variables included study design, clinical indication, institution type, sponsorship, and geographic location. Data were summarized descriptively. As only publicly accessible, deidentified registry data were used, ethics approval was not required. RESULTS Thirty-three lignocaine spray-related trials were identified, of which 31 (94%) trials were interventional and 2 (6%) observational. Airway management (10 studies) was the most common indication, followed by venepuncture analgesia (10 studies) and dental applications (7 studies). Three studies involved obstetrics–gynecology and three involved ENT procedures, with one observational study assessing postprocedural joint injection analgesia. Geographically, studies were predominantly concentrated in southern India, especially Tamil Nadu, Karnataka, Andhra Pradesh, Telangana, and Puducherry, with limited representation from eastern regions. Approximately 78% of trials originated from government or public sector academic institutions, 18% were self-funded postgraduate projects, and fewer than 5% had industry sponsorship. Nearly 40% of trials appeared linked to postgraduate thesis work. DISCUSSION The CTRI analysis shows that lignocaine spray is predominantly evaluated in airway, venous access, and dental procedures, reflecting its broad procedural utility. The high number of airway trials aligns with efforts to attenuate hemodynamic and periextubation responses,1 while venepuncture studies, particularly in children, support its role in reducing needle-related discomfort.9 Significant methodological variability in concentration and dosing mirrors global heterogeneity in topical anesthesia research.10 Although generally safe, concerns such as systemic toxicity and methemoglobinemia persist, yet safety-focused studies remain limited.11 The dominance of academic, government-led trials and southern regional clustering highlights concentrated research activity. Limitations CTRI registration was not mandatory for all nonregulatory studies before 2017, which may result in underrepresentation of earlier research. In addition, some trials may have used lignocaine spray, but not explicitly listed it under intervention keywords, leading to possible omission. Outcome data and completion status were limited. AI use declaration Artificial intelligence assistance (GeminiAI) was used for language refinement and structuring of the manuscript. All scientific content, data interpretation, and conclusions were verified, edited and approved by the authors. Financial support and sponsorship Nil. Conflicts of interest There are no conflicts of interest.