Rash after varicella vaccine: what to know

The varicella vaccine uses a weakened form of the virus to train the immune system. A few spot-like lesions may appear after vaccination and can resemble a very mild form of chickenpox. A rash may instead be unrelated, such as irritation from clothing, a viral illness, or an allergic reaction.

Note when the rash began, where it started, whether spots are fluid-filled, and whether there is fever or reduced energy. A clinician can compare the timing and appearance with the person’s health history and other recent exposures.

Keep the skin clean and avoid scratching or picking at spots. Do not burst blisters. Use loose clothing and ask a pharmacist about itch relief that is suitable for the person’s age and health. Avoid close contact between open lesions and people who are pregnant or have a weakened immune system until a clinician gives advice.

Call the vaccination provider if you are unsure whether the rash is expected. Do not arrange another dose or apply prescription treatment without discussing the reaction.

Get emergency help for breathing difficulty, swelling of the face or throat, collapse, or widespread hives. Seek urgent review for a rapidly spreading rash, severe headache, confusion, repeated vomiting, marked weakness, or blisters around the eyes. Contact a clinician if the person has a weakened immune system or the rash is accompanied by significant fever.

Ask whether the rash resembles a vaccine response or chickenpox, whether school or childcare attendance should change, and what symptoms should prompt another call. Share the vaccine date, photographs, and any medicines used for itch or fever.