A 12-year-old girl took two aspirin tablets. 4 hours later her body temperature increased to 39–40°C. She is complaining of general indisposition, dizziness, and spontaneous development of red spots and blisters on her skin. The skin lesions resemble burns of the second degree, in some places there are erosions or exfoliation of the epidermis. The Nikolsky sign is positive. Make the right diagnosis: