(ak-NEE-ih-form …) A skin condition that causes small, raised, acne-like bumps to form, usually on the face, scalp, chest, and upper back. The bumps on the affected skin are usually red and filled with pus and may crust over. They may also become painful, tender, and itchy. Sometimes, the affected skin becomes infected. Acneiform rash may be caused by an infection or by treatment with certain drugs, including some anticancer drugs, such as epidermal growth factor receptor (EGFR) inhibitors. Also called acneiform dermatitis and acneiform eruption.