Fever is a sign that something out of the ordinary is going on in your body. Fever is not always serious. As a general rule, in children a temperature over 37.5 – 38 °c is a fever. Fever can be caused by a number of factors. Fever has mostly been caused by a cold. Symptoms associated with fever in children include runny nose, cough or sore throat. The child with fever is crying inconsolably. Fever convulsion can occur in child who has a rapid increase in body temperature. The patents can control their kids’ body temperature in range, not above normal by giving an over-the-counter medicine and rub babies’ body. Parents shall use a thermometer to check their kids’ temperature to monitor an effectiveness of an over-the-counter medicine and rub baby’s body. If the symptom is serious such as high fever, fever lasts long for many days, listless, headache, shortness of breath, tried, or fever in under one year old kid, the parent should consult the doctor for investigating the cause of problem.

Fever is defined as having a temperature above the normal range. An average of normal body temperature is an oral temperature of 37°C. Our bodies tend to change throughout the day and are very good at keeping the temperature within a safe range. The change of body temperature is not much comparing with the change of external environment temperature because the body needs to control temperature for the proper body’s functions.

The thermometer readings generally indicate a fever is ≥ 37.2°C when measure in early morning or ≥ 37.8°C when measure in any time of the day.

Normal Body Temperature

  1. Normal body temperature does not stay same all day, and it normally fluctuates over the day with the highest levels between 3:00 p.m. – 5:00 p.m. and gradually decreases to the lowest between 11:00 p.m. – 01:00 a.m. then slightly increases again every day, repeatedly. The body temperature in children is more dynamic than adults.
  2. The body temperature in the morning is lower than in the late afternoon or evening.
  3. The body temperature is varied by muscle exertion or exercise or hormone.
  4. The body’ temperature control center is the hypothalamus. It is controlling the principal thermoeffectors for body temperature. It regulates the accumulation of heat, increases or decreases body temperature through the mechanisms of heat exchange.
  5. Peo-optic region is a portion of the hypothalamus that plays an important role in controlling body temperature. The studies that have continually conducted for over 60 years indicate that neurons in this region are sensitive to subtle changes in temperature. The pre-optic region elicits the thermoregulatory responses and is involved in many physiological and behavioral processes.
  6. Fever can be caused by various factors both outside and inside the body. The body responds fever by producing substances that affect to the body’ temperature control center and coordinates the autonomic nervous system. When your blood vessels near the surface of the skin are constricting, heat in your body can be lower released through your skin to the environment.
  7. Cold hands and feet often appear in patient with fever while forehead is still warm. Pale or blue color of the skin is a result of a lack of oxygenated blood. When temperature around skin is very low, your muscles will be shivering. Thus, shivering can actually be a step toward developing a fever. The shivering of muscles creates warmth by expending energy. The energy results to the rising of core body temperature and then may cause to the malfunction of body’ temperature control center and unresponsiveness of antipyretic drug.


  1. You may use thermometer to evaluate grade of fever. If there is no thermometer, you may evaluate by using back of the hand to touch forehead or other parts of body instead.
  2. Rectal thermometry is generally regarded as the most accurate means of temperature-taking. The temperature of rectal thermometry is typically higher than other thermometry because the heat is usually produced by bacteria in stool.
  3. Oral temperature is simple and rapid to conduct. The result is varied on core temperature. However, this method requires a good cooperation from the patient thus it is not workable with all patients, especially infants, uncooperative adults and patients on mechanical ventilators.
  4. Infrared ear thermometry is frequently used in critical care patients and out-patients because it is the easy and convenient method of taking temperature. The ear accurately reflects the core body temperature because the eardrum shares the blood supply with the temperature control center in the brain, making the ear an excellent site to measure temperature.
  5. Axillary thermometry proved both accurate and reliable in newborns but it is not suitable for adolescents and adults.
  6. An average temperature from rectal thermometry is 0.4°C higher than oral thermometry and 0.8°C higher than ear thermometry.

Types of Fever

  1. Continuous fever: Temperature remains above normal and fluctuates only few degrees but does not reduce to normal range.
  2. Intermittent fever: The temperature is elevating and later cycling back to normal.
  3. Remittent fever: Temperature fluctuates above normal throughout the day.
  4. Temperature is being high for days and low for days and so on.
  5. Low grade fever: It is mild elevation of body temperature than normal range throughout the day and not back to normal range.
  6. Fever can be classified by range of temperature into 3 grades. A low-grade fever is a temperature between 37.0°C and 38.9°C. Moderate-grade fever is a temperature between 38.9°C and 39.5°C. High-grade fever is a temperature between 39.5°C and 40.0°C.

Cause of Fever

  1. The infections with inflammation such as sore throat, ulcerative colitis, arthritis, bacterial infections, viral infections, protozoan infections (Flu, malaria, wound infection, abscess).
  2. The infections without specific symptom such as dengue fever, influenza, typhoid, etc. Some infections may not cause fever such as leprosy, ring worm, impetigo, etc. Infectious diseases commonly causes from bacteria, fungus, virus, yeast, protozoan, etc.
  3. Some abnormal symptoms occur in the body without an infection such as lymphoma that usually associated with other symptoms such as lymphadenopathy from inflammation, tumor, or cancer.
  4. The body’ temperature control center has been affected by an abnormal condition in brain such as brain tumor, hemorrhagic stroke, operation, etc.
  5. Drug or serum allergy, adverse effect of blood transfusion.
  6. Others such as outdoor exercise, some medicines, damage of tissues, abnormal metabolism, thyroidism, dehydration.
  7. Treating at the root cause of the problem. If the fever causes from serious illness, the patient should consult with doctor for receiving a direct treatment to the problem. Taking an antipyretic is only a part of total treatment.
  8. Taking an antipyretic medication such as Aspirin, Paracetamol, etc.
  9. Sponging to bring down the fever.


  1. Tepid sponging is an effective way to reduce body temperature. The physical method for treating fever is to reduce temperature by leading, carrying and evaporating heat. The evaporation is the best way to take heat from the patient’s body without shivering.
  2. Do not use cold water or ice for sponging because it may constrict blood vessel, prevent loss of heat, cause to shivering and rise body temperature.
  3. Sponge forehead and other part of body that is noticeably hotter than usual.
  4. Do not sponge the cold hands and feet.
  5. Avoid dressing warm clothes because the ventilation is low. If the patient shivers, wear extra clothes on him or her for warming but do not overdo.
  6. If the child has dehydrated, give your child plenty of water or IV fluid.

Antipyretic Medication

  1. Antipyretic medicine can only release the symptom of fever but does not cure the cause of fever. A dose of medication can control fever only for 4 – 6 hours. If the problem is not cured, the fever will usually return.
  2. The common antipyretic medicine includes of aspirin, paracetamol, NSAIDs.
  3. Most antipyretics work by inhibiting the conversion of arachidonic acid to prostaglandins. This mechanism of action for antipyretic drug is important because the elevations in body temperature usually occur when concentrations of prostaglandin E2 (PGE2) increase within hypothalamus. The mechanism of action of paracetamol lightly inhibits cyclooxygenase enzyme activity in peripheral tissues so its lack of anti-inflammatory activity.
  4. A regular dose of aspirin does not have adverse effects. However, an overdose of aspirin may cause high fever, listlessness, convulsion, and death. You should always take aspirin after meal promptly to for reducing possible stomach irritation.
  5. A regular dose of paracetamol does not have adverse effects. However, an overdose of paracetamol may cause liver damage and acute liver failure. In adults, they may take 2 tablets of paracetamol every 4 hours but should not take more than 3 consecutive days without consulting a doctor.
  6. The antipyretic medications should be given when patient has high fever only. They are generally administered according to the weight. Always leave at least 4 hours between doses. If the fever is not controlled, give plenty of water to the child and sponging. If fever has prolonged more than 2 – 3 days, please consult a doctor.


  1. Children between the aged of 6 months and 6 years may experience a complication of fever-induced convulsion (Febrile seizures).
  2. Children that had ever experienced convulsion or their parents or siblings with a history of fever-induced convulsion shall particularly be aware of convulsion when fever. They should be sponged and given antipyretic drug to control fever.
  3. Sometime antipyretic drugs may not be effective in children with high fever. They should firstly be sponged to reduce their body temperature.

Fever Herbal Treatment

Unlike conventional medicine, most of fever herbs have benefits in reducing fever but not controlling pain. The fever herbs are commonly bitter and difficult for taking. The most regular extraction of herbs is boiling without managing their taste and smell. The fever herbs are considered as an effective way to treat moderate or low grade fever that is less than 7 days without other serious diseases associated i.e. high shivering, severe headache, chest pain or severe abdominal pain.

  1. Tinospora Cordifolia: Pound and squeeze a bark of fresh Tinospora Cordifolia (25 inches long or 30 – 40 grams) then boil it in water down to one third. Drink decoction of Tinospora Cordifolia plant twice a day before breakfast and dinner or when rising of temperature.
  2. Tinospora baenzigeri: Boil a bark of fresh Tinospora baenzigeri (20 inches long) in the water down to one third. Drink it twice a day before meal or when rising of temperature.
  3. Tiliacora triandra: Boil a handful of Tiliacora triandra (15 grams) in the water and drink it three times a day before meal.
  4. Dracaena cochinchinensis: Chop 5 – 10 pieces of Dracaena cochinchinensis (2 x 3 inches per piece) and boil it in 6 glasses of water down to 4 glasses. Drink a half of glass when rising of temperature. In addition, dissolve a tea spoon of Prasa-chandang powder, Thai herbal medicine, with boiled water and drink when rising of temperature.

Source : Worrawut Charoensiri, M.D.