Journal of International Research in Medical and Pharmaceutical Sciences

Film-forming sprays (FFS) are topical and transdermal drug delivery platforms in which polymer-based formulations are applied to biological surfaces and spontaneously consolidate into thin, adherent, drug-loaded films upon solvent evaporation. Offering uniform coverage of irregular anatomical surfaces, customisable release kinetics, and an aesthetically superior patient experience compared with conventional semi-solid preparations, FFS have attracted growing scientific and clinical investment. Their polymeric backbone—encompassing cellulose derivatives, polymethacrylates, chitosan, alginate, polyvinyl alcohol, and thermoresponsive copolymers—determines film adhesion, mechanical flexibility, moisture vapour transmission, and drug permeation characteristics. The incorporation of nanostructured carriers, including solid lipid nanoparticles, nanostructured lipid carriers, liposomes, ethosomes, and polymeric nanoparticles, has further diversified achievable release profiles. This review critically appraises FFS technology across formulation principles, polymer systems, drug release mechanisms, therapeutic applications in wound care, dermatology, nail delivery, mucosal systems and ocular delivery, characterisation methodologies, regulatory frameworks, and emerging innovations. The evaluative conclusion reached is that clinical maturity is most evident in wound care and nail drug delivery; dermatological, mucosal, and ocular applications, whilst scientifically promising, remain supported predominantly by in vitro and pre-clinical data of uncertain clinical translatability. Several unresolved controversies characterise the field. The tension between hydroalcoholic and aqueous solvent systems—where formulation performance and patient safety interests diverge, particularly for application to compromised skin—remains without consensus. Whether nanocarrier-loaded FFS confer genuine clinical benefit over well-optimised conventional film matrices is an open and insufficiently investigated question, given the near-complete absence of robust human clinical data. The boundary between drug product and medical device classification for antimicrobial wound film sprays continues to generate regulatory uncertainty within both European and United States frameworks. On the question of stimuli-responsive FFS, this review takes the position that the translational gap between laboratory proof-of-concept and clinical practice is wider than the current literature acknowledges, and that the field would benefit from more critical self-appraisal of developmental readiness. Validated in vitro–in vivo correlations, standardised characterisation protocols, and dosage-form-specific regulatory guidance from the EMA and FDA represent the most pressing unmet needs constraining the responsible advancement of this promising drug delivery modality.