Hi,
Grey patches on the skin can occur due to many reasons. Melasma, sunlight allergy, eczema,
actinic keratosis have to be ruled out. Whether the patches are flat or raised, can aid in diagnosis. Associated symptoms such as itching, scaling, bleeding if present must be known. Melasma generally occurs on cheek, nose, forehead and chin. It is common in women.
Sun allergy can present as dark patches and are present on sun exposed areas such as arms, face, neck. Eczema or
dermatitis refers to inflammation of skin which can occur due to
dry skin, allergen exposure. Actinic keratosis also causes grey patches on sun exposed areas.
Complete blood count, blood sugar and thyroid tests should be taken to assist in treatment.
Hope I have answered your query. Let me know if I can assist you further.
Regards,
Dr. Saranya Ramadoss, General & Family Physician