Damp scalp application enhances follicular delivery of dutasteride loaded in liposomes compared to dry scalp

This study investigates the impact of scalp hydration on the delivery of dutasteride (DUT) when applied topically in a liposome formulation to treat androgenic alopecia. Using a modified Saarbrücken model on rodent and porcine skin, the research found that DUT accumulation in hair follicles nearly doubled in damp rat skin (9.4 ± 1.8 μg/cm2) compared to dry skin (4.7 ± 1.2 μg/cm2, p < 0.05), due to enhanced moisture retention facilitating diffusion. However, porcine skin showed similar DUT accumulation for both damp (10.0 ± 2.1 μg/cm2) and dry (11.8 ± 2.9 μg/cm2) conditions, attributed to its lower follicular density. These results suggest that scalp hydration significantly affects DUT delivery in follicle-rich models, indicating that application guidelines considering scalp moisture could improve the clinical efficacy of topical DUT treatments.