My doctor told me that tretinoin cream will fade hyper pigmented spots on my face. how long will the cream take to fade those areas?

Variable: It takes some time, usually 4-6 weeks to see a noticeable difference, it it is going to work! Other options are available.

Months: You will need to use a cream that is a mixture of tertian and hydroquinone. There are companies that mix the two together or you could obtain both creams and mix them yourself. Expect the process to take several months.

Not exactly: Retin A (tretinoin) tends to worsen hyper pigmentation, rather than improve it. We use a lightening cream called 4% hydroquinone to help lighten dark spots. Hydroquinone takes weeks to lighten skin.