Hello and Welcome to ‘Ask A Doctor’ service. I have reviewed your query and here is my advice. Polymorphous Light Eruption(also known as, sun poisoning ) findings are: small bumps or blisters, hives, and dry, inflamed skin looking like eczema. It involves the cheeks and ears, neck, sun-exposed areas of hands and arms. It is usually itchy. The rash of this condition appears 1-2 days after sun exposure and lasts for 1-2 weeks. Most common in spring and early summer. You can protect his skin with broad-spectrum sunscreen( with good UV-A protection), photoprotective clothing such a broad brim hat, long sleeve shirts and long pants, and avoid much midday sun exposure. If this is what he has and scratching is bothersome, hydrocortisone 1% cream(available over-the-counter) may give relief. Another possible cause for your son s symptoms could be Erythema Infectiosum. With this viral infection there are bright red patches on the cheeks. This rash can be preceded 1-2 weeks by fever, muscle aches, sore throat, chills. 1-4 days following the appearance of the facial rash. The rash spreads to trunk and extremities. Then ,this is followed by a lacy, reticular pattern of redness most noticed on the inner surfaces of the arms. There can be an itchy sensation with this condition, as well. Please keep in mind that I am giving you possibilities only. It will be important to take him to his primary care physician who will have the benefit of looking at your son to make the diagnosis. Hope I have answered your query. Let me know if I can assist you further.