Abstract: A pharmaceutical or food composition including alverine, 4-hydroxy alverine, a derivative thereof, or a salt thereof and their uses are disclosed. The composition is useful for preventing, alleviating, or treating muscular weakness-related diseases. When myoblasts are treated with the alverine, 4-hydroxy alverine, derivative thereof, or salt thereof, differentiation into myotubes is promoted. Therefore, the alverine, 4-hydroxy alverine, derivative thereof, or salt thereof can be effectively used in the promotion of differentiation of myoblasts and the prevention, alleviation, or treatment of muscular weakness-related diseases.