It depends on the cause - chickenpox and hand-foot-mouth spread, eczema and contact rashes do not. Purple non-blanching spots with fever, breathing trouble, or a hard-to-wake child mean urgent care now.
What to do
Common questions
Is my child's rash contagious?
It depends entirely on what is causing the rash, and that is the honest answer anyone should give you without seeing it. Rashes are a description, not a diagnosis. Some common childhood rashes are contagious: chickenpox spreads easily until every spot has crusted over - the AAP's symptom guidance notes that takes about 7 days after the rash appears - and hand, foot, and mouth disease circulates through daycares. Others, like eczema, heat rash, hives from a food reaction, and contact rashes, spread to no one. A few clues help you think about it before you see anyone. A rash plus a fever and a sick-looking child suggests infection. Itchy raised welts that come and go within hours suggest hives. A rash only where skin touched something new - a plant, a detergent, a metal - suggests contact. And timing matters: did it start after a new food, medication, or illness? Some rashes skip the guessing and go straight to urgent care: purple or blood-colored spots that do not blanch when pressed, especially with fever, any rash with trouble breathing or swelling of lips or tongue, or a rash with a stiff neck or a child who is hard to wake. An online clinician can look at photos and help you narrow it down. Pymander is a free AI doctor, 24/7 by text, and can help you sort the pattern before the visit.
