Unlocking relief: formulation, characterization, and in vivo assessment of salicylic acid–loaded microemulgel for psoriasis management

Psoriasis, a chronic skin condition, affects around 2–5% of the population. Topical corticosteroids treat the vast majority of cases (> 80%). Because of the physicochemical characteristics of the damaged stratum corneum, all treatments are ineffective. Nevertheless, systemic immunosuppression, the oral strategy, has substantial adverse effects that may be avoided using the topical procedure. The research sought to determine if a salicylic acid–loaded microemulsion-based gel (emulgel) could successfully infiltrate and maintain salicylic acid in skin tissue for psoriasis treatment. The pseudo-ternary phase was generated in different Smix ratios (1:1, 2:1, and 3:1; Labrasol:Transcutol® P). At a 3:1 ratio, the Smix had a substantial microemulsion area. Microemulsion was characterized for particle size, pH, etc. For topical application, the selected microemulsion was combined with Carbopol 940 gel, and ex vivo permeation and drug retention study were conducted. The effectiveness of the developed gel was checked using the IMQ-induced psoriatic plaque model. Salicylic acid microemulsion has an average globule size of 79.72 nm, pH 5.93, and 100% transmittance. In an ex vivo diffusion study, emulgel revealed greater penetration and more drug retention than ordinary salicylic acid gel. The emulgel was non-irritating on the skin of rats. In vivo studies revealed significant antipsoriatic activity of microemulsion-loaded gel compared to the marketed product. Developed emulgel was considered a potential product for an effective and safe way to administer salicylic acid for the treatment of skin diseases such as psoriasis.