Yes, a rash consistently appearing after taking paracetamol can indeed indicate an allergic reaction. You should stop giving this medication immediately. For the persistent fever, it is important to have your child evaluated by a pediatrician to identify the underlying cause and confirm the allergy. As a safe alternative, generic ibuprofen suspension can be used to manage the fever, but please consult your doctor first to confirm the correct dosage based on your child's weight. Seek immediate medical care if your child develops any swelling of the face or mouth, difficulty breathing, or if the rash becomes severe.