Fever in Adults: Common Causes, Home Care and When to Be Seen

What it involves

MedlinePlus defines a fever as a temporary increase in the body's temperature in response to a disease or illness. It says an adult probably has a fever when the temperature measured in the mouth is above 99 to 99.5 degrees Fahrenheit, depending on the time of day. Normal body temperature changes during the day and is usually highest in the evening, and a woman's menstrual cycle, physical activity, strong emotion, eating, heavy clothing, medicines, and a hot or humid room can all raise it. MedlinePlus calls fever an important part of the body's defense against infection.

Who this is for

• Adults with a temperature above normal who are not sure whether to be seen
• Patients whose fever has lasted more than two or three days
• Patients with a fever and a cough, sore throat, ear pain, burning with urination, or a rash
• Patients with diabetes, lung or heart disease, or a weakened immune system who get a fever

What to expect

• Questions about your temperature readings, how long the fever has lasted, and your other symptoms
• A physical exam that looks at the ears, nose, throat, neck, chest, and abdomen for a cause
• A review of your medicines, recent travel, and other health conditions
• A plan that may include lab work, a urine test, or a referral for imaging, plus advice on what to watch for

Common causes of fever

MedlinePlus says almost any infection can cause a fever. Its list includes:

• Respiratory infections such as colds and flu-like illnesses, sore throats, ear infections, sinus infections, mononucleosis, bronchitis, pneumonia, and tuberculosis
• Urinary tract infections
• Viral and bacterial gastroenteritis
• Skin infections such as cellulitis, bone infections, appendicitis, and meningitis
• Autoimmune or inflammatory disorders such as rheumatoid arthritis, lupus, ulcerative colitis, and Crohn disease
• Some medicines, including certain antibiotics, antihistamines, and seizure medicines, and blood clots

Fevers that need a closer look

MedlinePlus says the first symptom of a cancer may be a fever, particularly with Hodgkin disease, non-Hodgkin lymphoma, and leukemia, and that unexplained fevers lasting days or weeks are called fevers of undetermined origin. Most fevers come from common infections, but one that will not go away deserves an exam. The swollen lymph nodes guide and the unintentional weight loss guide describe signs checked alongside it.

Home care for a mild fever

MedlinePlus says that if the fever is mild and you have no other problems, you do not need treatment: drink fluids and rest. A simple cold can sometimes cause a high fever of 102 to 104 degrees Fahrenheit without meaning something serious. If you are uncomfortable, vomiting, dried out, or not sleeping well, you can lower the fever, though the goal is to lower it, not eliminate it. It advises removing excess clothing or blankets, keeping the room comfortable, and using a lukewarm bath after taking medicine. It says not to use cold baths, ice, or alcohol rubs, because they cause shivering that can raise core body temperature.

Fever-lowering medicine

MedlinePlus says acetaminophen and ibuprofen both help reduce fever in adults, and providers sometimes advise using both. Acetaminophen is taken every 4 to 6 hours and ibuprofen every 6 to 8 hours, and the package gives the dose for your weight. If you take other medicines or have kidney, liver, or stomach problems, ask your provider first. Water, soup, ice pops, and gelatin are good choices, and eating is fine but should not be forced. If vomiting or diarrhea is the main problem, the stomach flu and dehydration guide covers fluids.

When to call your provider

MedlinePlus says to contact your provider right away if you are an adult and:

• Your fever stays at or keeps rising above 103 degrees Fahrenheit, or reaches 105 degrees without coming down readily
• You have had a fever for longer than 48 to 72 hours, or fevers that come and go for a week or more
• You have a new rash or bruises, or pain with urination
• You have a serious illness such as a heart problem, diabetes, or COPD, or a weakened immune system
• You have recently traveled to another country

When to call 911

MedlinePlus says to call 911 or the local emergency number if you have a fever and you:

• Cannot be awakened easily or at all, or seem confused
• Cannot walk
• Have difficulty breathing
• Have blue lips, tongue, or nails
• Have a very bad headache or a stiff neck
• Have a seizure

What a visit involves

MedlinePlus says your provider will do a physical exam that may include a detailed look at the skin, eyes, ears, nose, throat, neck, chest, and abdomen. The tests it names are blood tests such as a complete blood count, a urinalysis, and a chest x-ray. Blood draws can be done during the visit at the West Palm Beach office, and the complete blood count guide and the urinalysis guide explain what those tests look at. A chest x-ray would be arranged through a referral. For a fever with a cough or sore throat, the cold versus flu guide and the sore throat guide are good next reads.

Sources

• MedlinePlus — Fever