How Long Should Tacrovate Forte And Elocom Be Used To Treat Vitiligo?

Hi, I've vitiligo on my lips and genitalia. I've been applying tacrovate forte(for morning use) and elocom (for night use) on my private parts.I also apply kenalog and tacrolimus ointment on my lips. My question is, for how long must I use these drugs. I've used them for one month and three weeks.