Desonide - What can I do about skin discoloration from the use of this product?

https://www.drugs.com/mtm/desonide-topical.html

Desonide topical side effects
Get emergency medical help if you have any of these signs of an allergic reaction: hives; difficulty breathing; swelling of your face, lips, tongue, or throat. Stop using this medication and call your doctor at once if you have severe irritation of any treated skin, or if you show signs of absorbing desonide topical through your skin, such as:

*blurred vision, or seeing halos around lights;
*mood changes;
*sleep problems (insomnia);
*weight gain, puffiness in your face; or
*muscle weakness, feeling tired.

Less serious side effects may include:

*mild skin itching, redness, burning, or peeling;
*dryness or scaly skin;
*thinning or softening of your skin;
*skin rash or irritation around your mouth;
*swollen hair follicles;
*changes in color of treated skin;
*blisters, pimples, or crusting of treated skin; or
*stretch marks.

It's worth mentioning to your son's doctor. He/she might change him to something else.