Background/Objectives: Although androgenic alopecia is the most prevalent among non-cicatricial alopecia, it still lacks an effective and safe treatment. Dutasteride (DUT) shows promising results in hair regrowth; however, oral DUT intake causes serious sexual adverse events. Hence, we produced liposomes with different bilayer structures and evaluated the capability of such systems in increasing DUT accumulation in the hair follicles. Methods: In vitro skin penetration tests were performed with porcine ear skin, and the follicular targeting factor (Tf) was calculated as the ratio between DUT amount in HFs and DUT recovered from the sum of all skin layers. Results: While the stiffer DUT-loaded liposome was not able to target the hair follicles in 12 h (Tf = 0.15), a DUT-loaded liposome with an edge activator in its composition, i.e., transfersomes, promoted better control over DUT release and a higher Tf (0.32) (p < 0.005). Conclusions: Transfersomes present higher affinity with DUT providing a better controlled release; hence, they are a better option for DUT follicle targeting compared to liposomes. Further formulation optimizations are needed aiming to prolong such targeting effect.

Background/Objectives: Treatment options for androgenic alopecia are still very limited and lack long-term efficacy. Dutasteride (DUT) has gained interest as a potent inhibitor of 5α-reductase, allowing for spaced applications, but DUT oral intake can cause serious adverse effects. Herein, we developed, characterized, and assessed the potential of DUT-loaded ethosomes with increasing ethanolic concentrations for hair follicle (HF) targeting to treat androgenic alopecia, hypothesizing that ethanol’s interaction with HFs’ sebum might increase DUT targeting to the HFs. Methods: Ethosomes were obtained using the water-dropping method. After a hydrodynamic size screening, a 30% ethanol concentration was fixed. Ethosomes with 30% ethanol were also prepared and had their ethanolic content removed by rotary evaporation for the evaluation of ethanol in targeting DUT to the HFs. The targeting factor (Tf) was calculated as the ratio between the DUT amount in HFs and the total DUT amount recovered from all skin layers after in vitro porcine skin penetration tests for 12 and 24 h. Results: The ethanolic concentration affected the vesicles’ size and the targeting potential. While the dried ethosomes could not increase DUT accumulation in the HFs at both time points (Tf: 0.27 in 12 h and Tf: 0.28 in 24 h), the presence of 30% ethanol in the vesicles increased the Tf from 0.28 (12 h) to 0.34 (24 h), significantly superior (p < 0.05) than the dried ethosome and control (Tf: 0.24) in 24 h. Conclusion: Ethosomes with a 30% ethanolic concentration were slightly more efficient in targeting HFs for dutasteride delivery.

Background/Objectives: The treatment of atopic dermatitis frequently involves using a topical corticosteroid and a moisturizer. While the sequential application of these products is a common dermatological practice, their influence on drug penetration remains poorly understood. There is no clear evidence on how hydration, application sequence, and massage affect cutaneous drug delivery. Hence, this study aimed to evaluate the effects of formulation type, moisturizer composition, application sequence, and mechanical stimulation on betamethasone dipropionate (BET) cutaneous penetration. Methods: Two commercial formulations (cream and ointment) of BET were evaluated in different experimental conditions, including drug application combined with moisturizers (Cetaphil^®, as an emollient; Nivea^®, as an occlusive) pre- or post-application, with or without a 30 s massage. In vitro skin penetration assays were conducted for 12 h using porcine skin mounted in modified Franz diffusion cells. BET levels were extracted from the skin layers and quantified by HPLC. Results: The cutaneous BET penetration was strongly influenced by the application sequence, type of moisturizer, and mechanical stimuli. Pre-application of an occlusive or emollient moisturizer, followed by 30 s physical stimuli, significantly enhanced drug retention in the stratum corneum. For the cream, pre-application of moisturizers followed by massage notably increased BET levels in both the stratum corneum and viable skin. Conversely, post-application of moisturizers hindered BET absorption. The ointment showed limited penetration across all conditions, with no drug detected in the viable skin. Conclusions: The results showed pre-hydrating the skin, combined with a 30 s massage, was the best strategy for BET diffusion into the skin following cream administration. The formulation type and the order of application directly influence the effectiveness of drug therapy and the topical absorption of BET.

1. Dutasteride (DUT), a dual 5α-reductase inhibitor, has emerged as a potent therapeutic option for alopecia; however, its use in this indication remains off-label [1,2]. Growing evidence highlight...

Introduction: Melatonin (MEL) is a natural hormone with anti-aging, anti-wrinkle, and anti-inflammatory properties, making it promising for topical cosmetics