Know About Medicines with Chula Pharmacy: Using Fever-Reducing Medicines Effectively

What is Fever?

In Thailand, many people are familiar with fever and fever-reducing medicines, as fevers are quite common. Fever is a natural mechanism that occurs when the body fights foreign invaders such as germs or inflammation. The hypothalamus in the brain raises the body’s temperature to create an environment unsuitable for viruses or bacteria to grow, while also stimulating the immune system to work more effectively. It also signals that something abnormal is happening in the body.

Causes and Levels of Fever

Causes of fever range from common viral infections such as colds and influenza, to bacterial infections, autoimmune diseases, side effects from medicines, vaccinations, or even some cancers. Chronic stress may also trigger inflammation leading to fever. Fever is diagnosed when body temperature exceeds 36.2–37.5°C. Fever levels are classified as:

• Low-grade fever: 37.6–38.3°C
• Moderate fever: 38.4–39.4°C
• High fever: 39.5–40.5°C
• Very high fever: above 40.5°C

Non-Medication Fever Reduction

Non-drug fever reduction methods include sponging the body with lukewarm water (armpits, neck, groin), staying in a well-ventilated room, wearing light clothing, and drinking plenty of water or electrolyte solutions. In young children, extra caution is needed as high fever may cause convulsions.

Using Fever-Reducing Medicines

The first-line medicine to use (if not allergic and no liver disease) is paracetamol. If paracetamol cannot be used, or does not reduce fever, ibuprofen may be considered. This NSAID is available for both children and adults.

• Children: 5–10 mg/kg per dose every 6–8 hours (maximum 40 mg/kg/day)
• Adults: 200–400 mg per dose every 6–8 hours

Dosage should ideally be calculated by a pharmacist. Ibuprofen has higher allergy risk than paracetamol, may irritate the stomach (must be taken after meals), and may cause kidney issues, especially in the elderly. It must not be used if the cause of fever is unknown or if dengue fever is suspected.

When to See a Doctor

If fever remains above 38.5°C for more than 2 days despite medication, or is accompanied by lethargy, vomiting, or breathing difficulty, consult a doctor immediately.

Thai Herbal Remedies

Thai herbal remedies for fever include Andrographis paniculata (Fah Talai Jone), Tinospora crispa (Borapet), and Chanthaleela formulations. Some have traditional use as well as partial scientific support.

Conclusion

Fever is a common symptom with many causes. The recommended fever reducer (if not allergic) is paracetamol. Non-drug measures such as sponging and drinking plenty of fluids should also be applied. If symptoms do not improve within 2–3 days, seek medical care immediately—especially during dengue fever outbreaks.  

Assoc. Prof. Dr. Nattada Areepiam and Assoc. Prof. Dr. Bodin Tiwasuwan

Faculty of Pharmacy Chulalongkorn University