According to California Pacific Medical Center, most viral fevers range between 101 degrees and 104 degrees and disappear after two or three days. A fever of 103.5 degrees Fahrenheit technically sits on the border between a common fever and a high fever. It often requires home treatment, but a doctor's visit may not be necessary unless your child displays other disconcerting symptoms.
KidsHealth explains that fevers occur when the hypothalamus -- the body's internal thermostat -- raises the body's temperature in response to an infection or other internal threat. As such, a fever is only a symptom of illness rather than an illness itself, but fevers often cause additional symptoms. According to MayoClinic.com, other common symptoms associated with fevers include sweating, shivering, headache, body ache, loss of appetite and general weakness. A fever of 103.5 may also cause hallucinations, frustration, convulsions and dehydration.
Infections cause the majority of fevers. Standard culprits of childhood fevers include sinus infections, ear infections, bronchitis, sore throats and other cold or flu-like illnesses that affect your child's respiratory system. MedLinePlus Medical Encyclopedia also lists urinary tract infections, viral and bacterial gastroenteritis, bone infections, skin infections, tuberculosis, meningitis and appendicitis as other potential causes. Autoimmune disorders such as Crohn's disease and cancers such as leukemia can also cause fevers of 103.5 degrees or greater.
Home treatment reduces most fevers. New York Presbyterian Hospital states that you should treat any childhood fever equal to or greater than 102.2 degrees Fahrenheit. Give your child plenty of fluids to prevent dehydration caused by sweating. Your child may respond best to cold fluids such as ice water and popsicles. Dress your child in lightweight clothes and provide a light blanket, but avoid overdressing. A lukewarm spongebath may also make your child feel more comfortable. Older children may receive fever-reducing acetaminophen or ibuprofen, but always follow the package instructions when administering medication to your child.
Contacting Your Doctor
A fever of 103.5 degrees is a serious matter for children under one year in age. According to MedlinePlus, you should contact the doctor if a child under three months has a fever of 100.4 degrees or higher or if a child between three months and one year has a fever of 102.2 degrees or higher. A fever of 103.5 is not of grave concern in older children, but if the fever lasts 48 to 72 hours or climbs to 105 degrees, call your pediatrician. Additionally, if your child refuses fluids, displays signs of dehydration, complains of severe pain or demonstrates lethargy or difficulty waking up, you should call your doctor's office or emergency room.