Hi, thanks for your query.
Cosmelite cream is composed of
hydroquinone ,
tretinoin and momatosone.
Irritation is commonly due to tretinoin component. However the intensity of irritation varies individually.
Use a soap free cleanser for face and avoid sun exposure as much possible. Use a broad spectrum sunscreen when outside. This might help in reducing irritation.
If it persists inspite of these measures, you may have to discontinue it for a week or so. Then restart its application for lesser time say two hours, then slowly increase the duration till overnight if there is no irritation.
If this doesnot help you may have to use other substitutes like only hydroquinone cream or
kojic acid cream consulting your doctor.
cosmelite is a prescription cream.This cream is indicated for
hyperpigmentation,
melasma etc. which may be applicable to your brother but its better if he uses it under dermatological guidance.
Hope this answers your query.
Feel free to ask further queries.
All the best
Regards