Improved transcutaneous delivery of cetirizine hydrochloride for the treatment of post-chemotherapy alopecia: Poke and emulgel approach

Abstract: Background: Chemotherapy-induced alopecia negatively impacts the mental health of cancer patients. Topical minoxidil, a widely recommended drug for hair regrowth, causes scalp irritation and contact dermatitis. Oral minoxidil causes multiple cardiovascular and neurological side effects. Cetirizine hydrochloride, an antihistamine with a better safety profile than minoxidil, may stimulate hair follicle activity by modulating prostaglandin levels. Objectives: The present study aimed to develop a cetirizine hydrochloride-loaded emulgel and evaluate its potential, in combination with microneedling, for the treatment of chemotherapy-induced alopecia. Methods: Different emulgel formulations comprising cetirizine HCl, liquid paraffin, carbopol 940, propylene glycol, oleic acid, Tween 20, Span 20 and propylparaben were optimized using central composite design and response surface methodology. Physicochemical evaluation of the prepared emulgel included physical examination, determination of pH, viscosity, spreadability, drug content and stability. Interactions and compatibility among formulation constituents were assessed using In-silico analysis and Fourier transform infrared spectroscopy. In-vitro drug release, ex-vivo permeation and in-vivo hair growth studies were carried out to evaluate the performance efficiency of emulgel. Results: The prepared emulgels exhibited acceptable physicochemical properties and remained stable for 3 months. Constituents were found to be compatible with each other. The optimized formulation F4 released >95% drug at pH 5.5 within 360 minutes. During an ex-vivo study, ~94% of the drug permeated across rat skin within 6 hours following application of emulgel on the microneedle-pretreated skin. In cyclophosphamide-induced alopecia in rats, application of emulgel to microneedle-pierced skin for 15 days promoted hair growth. Conclusion: The prepared cetirizine HCl-loaded emulgel and microneedle combination may be a promising approach to treating chemotherapy-induced alopecia.