A fever is a temporary elevation in the body’s internal temperature, defined as an oral temperature of 100.4°F (38°C) or higher. This rise occurs because the hypothalamus, the brain’s thermoregulatory center, resets the body’s thermostat in response to illness or infection. Chills are a physiological response where the body perceives itself as too cold relative to this new, higher temperature goal. Shivering, or rigors, is the body attempting to generate heat rapidly through muscle contraction to reach the elevated temperature needed to fight pathogens.
Immediate Comfort Measures
When managing fever and chills at home, focus on supportive care that enhances comfort and prevents dehydration. Rest is a component of recovery, as physical activity increases the body’s metabolic rate, which can further elevate core temperature. Conserving energy allows the immune system to work more effectively against the infection.
Hydration is important because fever increases fluid loss through sweating and increased respiratory rate. Clear fluids like water, electrolyte solutions, and broths are recommended for replacing lost water and salts. Avoid caffeinated beverages and alcohol, which act as diuretics and can worsen dehydration.
Temperature regulation should be managed carefully to avoid triggering the shivering reflex, which paradoxically generates more heat. During a chill, a light blanket may be used to reduce discomfort, but the patient should be dressed in light, breathable clothing. When the fever peaks and the patient feels hot, avoid excessive bundling to allow heat to escape.
For external cooling, use a lukewarm bath or sponge bath, ideally between 85°F and 95°F (29°C and 35°C). The cooling effect comes from water evaporation from the skin, which draws heat away from the body. Avoid using cold water or ice, as this can constrict blood vessels and induce shivering, potentially increasing the core temperature.
Managing Symptoms with Medication
Over-the-counter (OTC) antipyretics reduce fever and alleviate discomfort, but do not treat the underlying illness. Common choices include Acetaminophen (Tylenol) and Nonsteroidal Anti-Inflammatory Drugs (NSAIDs) such as Ibuprofen. These medications work by inhibiting prostaglandins, the chemical messengers that signal the hypothalamus to raise the body’s temperature.
When using these medications, strictly follow the dosage instructions to prevent serious side effects. For adults, the maximum daily dose of Acetaminophen should not exceed 4,000 milligrams, as excessive use leads to liver damage. Ibuprofen’s adult dosage should not exceed 1,200 milligrams per day for OTC use, due to the risk of stomach irritation and kidney issues.
Caution is required when medicating children, as pediatric dosing must be based on the child’s current weight, not their age. Use the provided measuring syringe or cup, since household teaspoons vary widely and can lead to accidental overdose. Parents must avoid giving children combination cold and flu products that already contain Acetaminophen, resulting in an inadvertent double dose.
Aspirin should never be given to children or teenagers, especially when recovering from viral illnesses like the flu or chickenpox. This is associated with Reye’s Syndrome, a rare but fatal condition causing swelling in the liver and brain. Acetaminophen and Ibuprofen remain the safer options for managing fever and pain in pediatric patients, though Ibuprofen is reserved for infants six months of age and older.
Warning Signs Requiring Medical Attention
While most fevers resolve naturally, certain signs indicate the need for medical evaluation. The patient’s age is a primary consideration, as fever in infants requires urgency. Any infant under three months of age with a rectal temperature of 100.4°F (38°C) or higher should be taken to an emergency care facility immediately.
For older children and adults, the duration and severity of the fever become more important factors. A fever that persists beyond three to five days, or one that does not decrease noticeably even after taking fever-reducing medication, warrants a call to a healthcare provider. An adult temperature that reaches or exceeds 103°F (39.4°C) should also prompt medical consultation.
Immediate emergency attention is required if the fever is accompanied by severe or neurological symptoms. These red flags include a stiff neck, a severe headache, mental confusion, or difficulty waking up. Other urgent signs are difficulty breathing, chest pain, seizures, or a non-fading rash resembling tiny red or purple spots. Persistent vomiting or diarrhea leading to dehydration, such as reduced urination or lethargy, also requires prompt medical intervention.