Hand, foot, and mouth disease is a rash disease caused by an intestinal virus infection, characterized by scattered maculopapular and vesicular rashes on the hands, feet, buttocks, and other areas. Typically, small vesicles appear on the oral mucosa, or they may already have ruptured into shallow ulcers, primarily located on the tongue, buccal mucosa, palate, and inner lips. Subsequently, rashes appear on the hands and feet, most commonly as maculopapules, which then develop into vesiculopapules about three to seven millimeters in size. The vesicles have a relatively thick covering and are surrounded by reddened skin, predominantly located at the extremities. Sometimes, they may extend to the arms, legs, buttocks, or perineal area. The distribution of the rash is centrifugal, with the number of lesions varying from a few to dozens. Generally, the lesions absorb on their own within two to three days without desquamation, scarring, or pigmentation. The vesicles and ulcers in the mouth mostly heal on their own within a week.