(nik´o-lo) a severe cutaneous reaction after intramuscular administration of medications, often in the gluteal region, because of ischemia from accidental arterial obliteration or vasculitis. Manifestations include severe local pain, swelling, livedoid changes, and increased skin temperature; there may also be fever, tachycardia, dyspnea, albuminuria, and eventually gangrene. Called also livedoid dermatitis and embolia cutis medicamentosa.