Fever with an itchy rash

Chickenpox can cause an itchy rash that appears in crops and changes over time. Viral illnesses may cause fever with widespread spots, while cellulitis more often causes a localized area that is hot, painful, red, and expanding; itching is not the main feature. Hives with swelling may indicate an allergic reaction. The rash pattern alone cannot confirm its cause.

Keep the skin cool, avoid scratching, and use loose clothing. Trim nails and wash hands to reduce skin damage and spread of infection. Drink fluids and rest. Do not apply a new cream or take an antihistamine without checking that it is suitable, particularly for a child, pregnancy, chronic illness, or other medicines. Avoid close contact with vulnerable people until an infection has been assessed.

Call emergency services for difficulty breathing, swelling of the lips or tongue, fainting, severe confusion, a seizure, or a rash that does not fade when pressed. Seek urgent medical assessment for a stiff neck, severe headache, purple or blistering skin, rapidly spreading redness, severe pain, dehydration, or a person who is unusually drowsy. Arrange medical advice when fever persists, returns, or the rash is not improving.

Ask whether the rash looks infectious or allergic, whether testing is needed, how to control itching safely, and how long to avoid school, work, or close contact.