The invention provides methods and pharmaceutical compositions for preventing or treating alopecia, such as chemotherapy-induced alopecia (CIA). The pharmaceutical compositions of the invention comprises an effective amount of a vitamin D compound in a formulation that topically delivers the vitamin D compound to the epidermis layer but substantially avoids the dermis layer. In chemotherapy patients, the pharmaceutical compositions of the invention can be administered either before or concurrent with the chemotherapy medication.本發明提供預防或治療禿髮症,諸如化學療法誘發之禿髮症(CIA)的方法及醫藥組合物。本發明之醫藥組合物於調配物中包含有效量之維他命D化合物,該調配物將維他命D化合物局部傳遞至表皮層,而實質上避免進入真皮層。在化學療法患者中,本發明之醫藥組合物可在化學治療藥物之前或同時投與。