Use Green Dot Pacifier with color-change dot like any regular pacifier. If baby has a fever of at least 100�F/37.8�C, the green dot changes from green to black in approximately 7-8 minutes. At higher temperatures, the color change occurs more rapidly. Drinking hot or cold fluids immediately before use may affect reading. Green Dot Pacifier is a monitor of oral temperature only. If fever is indicated, take temperature with a rectal thermometer. Rectal temperature may vary from oral temperature by 1.0�F/0.6�C or more. If feverish condition persists, notify physician.