Melanocyte cells present below the human skin produces and transfer more amount melanin pigment to the upper layer of skin. Thereby it creates a protective layer from the Sun/UV rays.
But in vitiligo melanin pigment is lost resulting into uneven discoloration of skin. Therefore, for treating vitiligo and other hypopigmentary disorders, it is important to use any product that will absorb the sun exposure and induce the pigmentogenesis process and at the same time, it will also protect the vitiligenous skin from over sun exposure. As over sun exposure to the depigmented skin can be harmful.
Natural resources that can help you out for treating vitiligo:
The plant Psoralea corylifolia (Babchi) contains the active constituent Psoralen which entraps and enhances the benefit of the Sun/UV rays when mild exposure is given. It makes the skin sensitive to sunlight. Sunlight being entrapped by psoralen kindles the genetic memory of the damaged melanocytes resulting into melanin production.
On the other hand, Piperine in Piper longum promotes melanocyte multiplication and transfers melanin pigment to the upper layer of skin; whereas Wrightia tinctoria augments healing properties of skin and Indigofera tinctoria works as anti-oxidant and retards the damage of skin cells due to free radicals.
Various herbal ointments with all or any of these herbs also provide sun protection other than inducing melanin production and thus they can be the best drug of choice for treating hypopigmentary disorders and vitiligo.
But do always consult with your doctor to choose the right treatment product for your problem.