It's difficult to make a determination of the cause of your skin color changes. As a dermatologist, I'd need to know more information including what type of minoxidil you are using. Skin lightening can be caused by multiple factors that likely needs an in-person evaluation to make the appropriate diagnosis. As examples, vitiligo, allergic contact dermatitis, pityriasis alba, post-inflammatory hypopigmentation, discoid lupus, and more can all cause skin lightening.
Thanks for sharing your story. We would need more information about the type of hair loss you're experiencing, symptoms, medical history, and examination to make a diagnosis and treatment plan. It's possible that you're experiencing a telogen effluvium (big shed) in response to hormone therapy, but I've seen several other forms of hair loss as a result. We're seeing an epidemic of scarring hair loss (eg lichen planopilaris and frontal fibrosing alopecia) which can progress to permanent hair loss. Treatments vary depending on what you have, but there are more options then finasteride and minoxidil. I recommend you get evaluated by a hair specialist who and give you the best advise in person.
