Hi,
Itchy rashes on the back, head, chest, stomach, arms, and legs can be caused by various factors, including skin conditions such as eczema,
psoriasis,
contact dermatitis, hives, and scabies. Other causes can include
insect bites, fungal infections, autoimmune diseases, and medications.
Given that
allergy tests have had negative results and that no bed bugs or mites have been found, it would be best to see a
dermatologist for a proper diagnosis and treatment plan. The constant scratching and development of bloody bumps indicate that the itching is severe and requires medical attention.
Take care. Hope I have answered your question. Let me know if I can assist you further.
Regards,
Dr. Priyanka, General & Family Physician