Cutaneous adverse drug reactions (CADR) are an unfavorable condition caused by drugs manifesting on the skin. Exanthemata's drug eruption is the most common manifestation. The symptoms are itchy rash and burning sensation at the lesion and can occur along with fever and pain. The most common types of drugs inducing CADR are antibiotics, non-steroidal, anti-inflammatory drugs (NSAID), and anticonvulsants. A 48-year-old woman with complaints of itching on the chest followed by both arms and legs. Complaints arose 8 days after surgical excision of the craniometrical tumors when the patient was treated with polypharmacy medications. The description of the lesions is regional, multiple, well-defined maculopapular lesions with erythema, crusts, and excoriation. The working diagnosis is exanthemata's drug eruption with ceftriaxone, paracetamol, and phenytoin as the suspected causative drugs. No history of drug allergy was known before. Polypharmacy can cause difficulty in making clinical decisions for discontinuing the suspected drugs and cause patient's comorbidity left untreated. Therefore, it is important to identify the type of drugs and drug interaction causing cutaneous adverse drug reactions and minimize the use of polypharmacy therapy if possible.