Hi,
As per your query you have symptoms of 
severe itching throughout the body which seems to be due to many reasons like
- contact dermatitis
- coming into contact beauty products
-side effects or certain medicines
- allergic reaction
- sensitivity to sunlight
- systemic conditions such as eczema and psoriasis. 
Need not to worry. I would suggest you to 
- Maintain proper personal hygiene.
- Apply cold compresses to reduce the itchiness and inflammation. 
- Take an anti-inflammatory medication such as Zyrtec.
- Drink plenty of fluids.
- Avoid touching or pricking rashes and apply calamine lotion to soothe them.
- Avoid application of any hard cosmetics.
You should 
consult a dermatologist for proper examination Doctor may order skin 
patch test, 
blood test, test for allergy and physical examination. The doctor may prescribe corticosteroid ointment, antibiotics, anti-inflammatory and immunosuppressants. 
Hope I have answered your query. Let me know if I can assist you further.
Regards,
Dr. Harry Maheshwari, 
Dentist