Acute generalized exanthematous pustulosishttps://en.wikipedia.org/wiki/Acute_generalized_exanthematous_pustulosis
Acute generalized exanthematous pustulosis (AGEP) is a rare skin reaction that in 90% of cases is related to medication administration. Acute generalized exanthematous pustulosis is characterized by sudden skin eruptions that appear on average five days after a medication is started. These eruptions are pustules, i.e. small red white or red eruption of the skin that contain cloudy or purulent material (pus). The skin lesions usually resolve within 1–3 days of stopping the offending medication.

  • Widespread lesions with erythema and pustules appear suddenly.
  • Erythema and pustules without itching occur suddenly.
References Acute Generalized Exanthematous Pustulosis 37276304 
NIH
Acute generalized exanthematous pustulosis (AGEP) is an adverse cutaneous reaction characterized by sterile pinpoint nonfollicular pustules atop an erythematous background. Symptoms most often occur in the setting of medication exposure, such as systemic antibiotics, rapidly become generalized, followed by desquamation and resolution within about two weeks of discontinuing the offending trigger. Although mostly self-limited without systemic involvement, severe cases are classified alongside other cutaneous adverse reactions such as Stevens-Johnson syndrome, toxic epidermal necrolysis, and drug reaction with eosinophilia and systemic symptoms. Treatment is primarily supportive, and the prognosis for complete resolution is excellent.
 Acute Generalized Exanthematous Pustulosis: Clinical Characteristics, Pathogenesis, and Management 36702114
Recent experimental data reviewed herein are supportive of an early role of drug-induced innate immune activation and innate cytokines such as interleukin (IL)-1, IL-36, and IL-17 in the pathogenesis of AGEP. This explains the rapid onset and neutrophilic character of the cutaneous inflammation.
 Acute Generalized Exanthematous Pustulosis - Case report 36876416 
NIH
A 76-year-old male patient presented as an emergency due to a 2-day history of skin changes. Physical examination revealed disseminated erythematous macules and plaques on the trunk and extremities. In the further course, confluence of the macules and non-follicular pustulosis developed in the area of erythema. Laboratory tests revealed leukocytosis with neutrophils and elevated C-reactive protein.