What causes shivering during a fever. How to treat fever and chills at home. When should you seek medical attention for a fever. What are the differences between mild and high fevers in adults. How does the body use shivering to fight infections.

The Connection Between Shivering and Fever

Shivering is often associated with feeling cold, but it can also occur when you have a fever. This involuntary response is part of your body’s natural defense mechanism against illness. But why does this happen?

When you shiver, your muscles rapidly contract and relax, generating heat in the process. This helps raise your body temperature, which can be beneficial in fighting off viral or bacterial infections. The increased body heat creates an environment less hospitable for pathogens to thrive.

How Does Shivering Help Fight Infections?

Your body’s internal thermostat, the hypothalamus, plays a crucial role in this process. When it detects an infection, it raises the temperature “set point.” In response, your muscles begin to shiver, quickly elevating your body temperature to reach this new, higher set point. Once achieved, the shivering typically subsides.

Common Causes of Fever and Shivering

While infections are a primary cause of fever and shivering, several other conditions can trigger these symptoms:

• Heat exhaustion
• Certain medications (e.g., antibiotics, blood pressure-lowering drugs)
• Inflammatory conditions (e.g., rheumatoid arthritis, cancer)
• Some immunizations (e.g., diphtheria, tetanus, pneumonia vaccines)
• Post-surgical reactions to anesthesia
• Sudden drops in blood sugar levels

Can You Have a Fever Without Shivering?

Indeed, it’s possible to experience a fever without accompanying chills or shivering. The presence or absence of shivering doesn’t necessarily indicate the severity of the fever or underlying condition.

Treating Fever and Shivering at Home

Not all fevers require medical intervention. For adults and children over 2 years old, rest and adequate fluid intake are often sufficient for fevers below 102°F (38.9°C). However, when additional treatment is necessary, consider the following options:

1. Over-the-counter medications: Acetaminophen (Tylenol) or ibuprofen (Advil, Motrin) can help reduce fever. Always follow dosage instructions carefully, especially for children.
2. Light clothing and bedding: Use a light sheet instead of heavy blankets to prevent overheating.
3. Adjust room temperature: Increase the ambient temperature in your home for comfort.
4. Stay hydrated: Drink plenty of fluids to prevent dehydration.

Special Considerations for Infants and Young Children

For babies between 3 and 6 months old, the same treatment approach applies unless they display unusual behavior. Children aged 6 to 24 months should be treated similarly, but seek medical advice if the fever persists above 102°F (38.9°C) rectally for more than a day. It’s crucial to note that medications should not be given to infants under 6 months without consulting a healthcare professional.

Understanding Fever Classifications in Adults

Fevers in adults are typically categorized into two main groups:

• Mild or low-grade fever: Temperature between 99.5°F (37.5°C) and 100.9°F (38.3°C)
• High or high-grade fever: Temperature over 103.0°F (39.4°C)

Understanding these classifications can help you determine the appropriate course of action and when to seek medical attention.

When to Seek Medical Help for Fever and Shivering

While many fevers can be managed at home, certain situations warrant immediate medical attention. Be alert for the following signs and symptoms accompanying fever and chills:

• Stiff neck
• Confusion or irritability
• Sluggishness
• Severe cough or shortness of breath
• Intense abdominal pain

Additionally, seek medical help if:

• An adult’s temperature remains above 103°F (39.4°C) for over an hour despite home treatment
• An adult’s fever persists for more than 3 days
• A baby younger than 3 months has a rectal temperature of 100.4°F (38.0°C) or higher
• A child between 3 months and 1 year has a fever above 102.0°F (38.9°C) lasting more than 24 hours

The Body’s Temperature Regulation System

The human body’s ability to regulate temperature is a complex and fascinating process. The hypothalamus, often referred to as the body’s thermostat, plays a central role in this system. How does it work to maintain our body temperature and respond to infections?

The Role of the Hypothalamus

Located in the brain, the hypothalamus continuously monitors our internal temperature. When it detects an infection, it raises the temperature set point as part of the immune response. This triggers a series of physiological changes, including shivering, to help the body reach and maintain this new, elevated temperature.

Why Does Fever Help Fight Infections?

An increased body temperature creates an environment less favorable for many pathogens to survive and reproduce. Additionally, higher temperatures can enhance certain immune system functions, making it easier for your body to combat the infection.

Impact of Medications and Medical Procedures on Body Temperature

Various medications and medical procedures can affect our body’s temperature regulation system. Understanding these effects can help explain unexpected fever or shivering episodes.

Anesthesia and Post-Surgical Shivering

Shivering is a common occurrence after surgery, often attributed to the wearing off of anesthesia. Some types of anesthesia can interfere with the body’s normal temperature regulation. When combined with the typically cool environment of operating rooms, this can lead to a decrease in body temperature and subsequent shivering as the body tries to warm itself.

Medications That Can Cause Fever

Certain medications can induce fever as a side effect. These may include:

• Some antibiotics
• Certain blood pressure medications
• Some anti-inflammatory drugs

If you suspect a medication might be causing your fever, consult with your healthcare provider before making any changes to your treatment regimen.

Fever and Shivering in Special Populations

Different age groups and populations may experience fever and shivering differently, and may require specific considerations in their care and treatment.

Infants and Young Children

Fever in infants and young children often causes more concern due to their developing immune systems and inability to communicate their symptoms effectively. Parents and caregivers should be particularly vigilant about monitoring temperatures and seeking medical advice when necessary.

Elderly Individuals

Older adults may not always exhibit typical fever symptoms. They might not develop a high temperature even when fighting an infection, making it crucial to watch for other signs of illness. Conversely, they may be more susceptible to complications from high fevers, necessitating closer monitoring and potentially earlier intervention.

Immunocompromised Patients

People with weakened immune systems, such as those undergoing chemotherapy or living with HIV/AIDS, may have altered responses to infections. They might develop fevers more easily or struggle to mount an effective fever response. These individuals should work closely with their healthcare providers to develop appropriate monitoring and treatment plans.

Prevention and Long-Term Management of Recurrent Fevers

While not all fevers can be prevented, there are steps you can take to reduce your risk of infections that commonly cause fever and shivering:

• Practice good hygiene, including regular hand washing
• Stay up-to-date on vaccinations
• Maintain a healthy lifestyle with proper nutrition and regular exercise
• Get adequate sleep to support your immune system

Managing Chronic Conditions

For individuals with chronic conditions that may cause recurrent fevers, such as autoimmune disorders or certain cancers, long-term management strategies are crucial. These may include:

• Regular check-ups with healthcare providers
• Adherence to prescribed treatment plans
• Monitoring and tracking fever patterns
• Learning to recognize early signs of infection or flare-ups

By working closely with your healthcare team, you can develop a personalized approach to managing your condition and minimizing the impact of recurrent fevers on your daily life.

Causes, Treatment, and When to Seek Help

People typically associate shivering with being cold, so you may wonder why you shiver when you have a fever. Shivering is part of the body’s natural response to an illness. When a person shivers, it helps their body temperature rise, which helps fight off a virus or a bacterial infection.

Still, it’s important to know what to do if you’re feeling hotter than normal, and your body is shaking with chills. Read on to learn more about shivering and fevers.

Shivering helps the body warm itself.

When you shiver, your muscles contract and relax in rapid succession, and all those little movements can create heat. It’s an involuntary response triggered by your immune system reacting to an infection or a cold environment.

An increase in body temperature can help your body fight infections because infections don’t survive as well above your normal temperature of 98.6°F (37.0°C).

The part of your brain that sets your body’s temperature is called the hypothalamus. When the body has an infection, the hypothalamus responds by moving the “set point” for a higher temperature.

The muscles in your body respond by contracting and relaxing faster, which helps your body reach this higher temperature more quickly. Once your body temperature reaches its new set point, your shivering should stop.

Other conditions, such as a sudden drop in your blood sugar levels, can also bring on shivering. You may also experience shivering after surgery as a response to the anesthesia wearing off.

Additionally, certain types of anesthesia can interfere with your body’s usual temperature regulation system. When paired with a cool operating room environment, a decrease in body temperature can lead to shivering.

Can you have a fever without shivering?

You may have a fever without shivering and the chills, too. Conditions that may trigger a fever include:

• heat exhaustion
• medications, such as certain antibiotics or blood pressure-lowering drugs
• some inflammatory conditions, such as rheumatoid arthritis or cancer
• certain immunizations, including diphtheria, tetanus, and pneumonia (DTaP)

Not every fever needs treatment.

According to Mayo Clinic, rest and fluids are usually enough to treat a fever in adults and infants over the age of 2, unless the fever reaches above 102°F (38.9°C).

This treatment also applies to babies between 3 and 6 months old, as long as they are not acting out of the ordinary. Treat children ages 6 to 24 months in the same way, unless the fever stays above 102°F (38.9°C) rectally for more than a day.

When rest and fluids aren’t enough, try acetaminophen (Tylenol) or ibuprofen (Advil, Motrin). Read the labels carefully, especially when treating a child.

You should also check with a doctor or a pharmacist if you have any questions about dosing or combining medications.

Do not give medications to infants less than 6 months old.

Speak to a doctor immediately if an infant under 3 months old has a rectal temperature of 100.4°F (38°C) or higher.

Mild vs. high fever in adults

• Mild or low-grade fever: A temperature between 99.5°F (37. 5°C) and 100.9°F (38.3°C)
• High or high-grade fever: Temperature over 103.0°F (39.4°C)

Was this helpful?

If you have a mild fever with shivering, you don’t necessarily need to see a doctor or take a fever-reducing medication. You might prefer to get comfortable and wait it out. You can try:

• resting with a light sheet, rather than a heavy blanket, which can continue to raise your body temperature
• putting on an extra layer of clothes, like a sweatshirt, that you can remove if you start to overheat
• turning up the temperature in your home
• drinking plenty of fluids

When other serious signs accompany a fever and chills, you should see a doctor as soon as possible. These include:

• a stiff neck
• confusion
• irritability
• sluggishness
• a bad cough
• shortness of breath
• severe abdominal pain

You should also seek medical help if:

• you’re an adult, and you have a temperature that remains above 103°F (39. 4°C) for more than an hour following home treatment
• you’re an adult, and you have a fever that lasts more than 3 days
• a baby younger than 3 months has a rectal temperature of 100.4°F (38.0°C) or higher
• a child between the ages of 3 months and 1 year has a fever above 102.0°F (38.9°C) that lasts for more than 24 hours

If you feel your temperature starting to rise into a fever, and you’re shivering, keep in mind that your body is probably responding to an infection.

Rest and fluids are the best ways to help your body recover, but you can take acetaminophen or ibuprofen as well, especially if your temperature rises above 102°F (38.9°C).

Pay close attention to other signs, which may indicate that you need to see a doctor.

If it’s your child who is shivering with what feels like a fever, be sure to get an accurate temperature reading, so you’ll know whether to get your little one to a doctor immediately.

Causes, Treatment, and When to Seek Help

People typically associate shivering with being cold, so you may wonder why you shiver when you have a fever. Shivering is part of the body’s natural response to an illness. When a person shivers, it helps their body temperature rise, which helps fight off a virus or a bacterial infection.

Still, it’s important to know what to do if you’re feeling hotter than normal, and your body is shaking with chills. Read on to learn more about shivering and fevers.

Shivering helps the body warm itself.

When you shiver, your muscles contract and relax in rapid succession, and all those little movements can create heat. It’s an involuntary response triggered by your immune system reacting to an infection or a cold environment.

An increase in body temperature can help your body fight infections because infections don’t survive as well above your normal temperature of 98.6°F (37.0°C).

The part of your brain that sets your body’s temperature is called the hypothalamus. When the body has an infection, the hypothalamus responds by moving the “set point” for a higher temperature.

The muscles in your body respond by contracting and relaxing faster, which helps your body reach this higher temperature more quickly. Once your body temperature reaches its new set point, your shivering should stop.

Other conditions, such as a sudden drop in your blood sugar levels, can also bring on shivering. You may also experience shivering after surgery as a response to the anesthesia wearing off.

Additionally, certain types of anesthesia can interfere with your body’s usual temperature regulation system. When paired with a cool operating room environment, a decrease in body temperature can lead to shivering.

Can you have a fever without shivering?

You may have a fever without shivering and the chills, too. Conditions that may trigger a fever include:

• heat exhaustion
• medications, such as certain antibiotics or blood pressure-lowering drugs
• some inflammatory conditions, such as rheumatoid arthritis or cancer
• certain immunizations, including diphtheria, tetanus, and pneumonia (DTaP)

Not every fever needs treatment.

According to Mayo Clinic, rest and fluids are usually enough to treat a fever in adults and infants over the age of 2, unless the fever reaches above 102°F (38. 9°C).

This treatment also applies to babies between 3 and 6 months old, as long as they are not acting out of the ordinary. Treat children ages 6 to 24 months in the same way, unless the fever stays above 102°F (38.9°C) rectally for more than a day.

When rest and fluids aren’t enough, try acetaminophen (Tylenol) or ibuprofen (Advil, Motrin). Read the labels carefully, especially when treating a child.

You should also check with a doctor or a pharmacist if you have any questions about dosing or combining medications.

Do not give medications to infants less than 6 months old.

Speak to a doctor immediately if an infant under 3 months old has a rectal temperature of 100.4°F (38°C) or higher.

Mild vs. high fever in adults

• Mild or low-grade fever: A temperature between 99.5°F (37.5°C) and 100.9°F (38.3°C)
• High or high-grade fever: Temperature over 103.0°F (39.4°C)

Was this helpful?

If you have a mild fever with shivering, you don’t necessarily need to see a doctor or take a fever-reducing medication. You might prefer to get comfortable and wait it out. You can try:

• resting with a light sheet, rather than a heavy blanket, which can continue to raise your body temperature
• putting on an extra layer of clothes, like a sweatshirt, that you can remove if you start to overheat
• turning up the temperature in your home
• drinking plenty of fluids

When other serious signs accompany a fever and chills, you should see a doctor as soon as possible. These include:

• a stiff neck
• confusion
• irritability
• sluggishness
• a bad cough
• shortness of breath
• severe abdominal pain

You should also seek medical help if:

• you’re an adult, and you have a temperature that remains above 103°F (39.4°C) for more than an hour following home treatment
• you’re an adult, and you have a fever that lasts more than 3 days
• a baby younger than 3 months has a rectal temperature of 100. 4°F (38.0°C) or higher
• a child between the ages of 3 months and 1 year has a fever above 102.0°F (38.9°C) that lasts for more than 24 hours

If you feel your temperature starting to rise into a fever, and you’re shivering, keep in mind that your body is probably responding to an infection.

Rest and fluids are the best ways to help your body recover, but you can take acetaminophen or ibuprofen as well, especially if your temperature rises above 102°F (38.9°C).

Pay close attention to other signs, which may indicate that you need to see a doctor.

If it’s your child who is shivering with what feels like a fever, be sure to get an accurate temperature reading, so you’ll know whether to get your little one to a doctor immediately.

Fever and chills – features of the course

High fever accompanied by chills is often a symptom of influenza or SARS

High body temperature accompanied by chills is a symptom of influenza or SARS ^{1. 2} and helps to identify this disease.

Features of the course

Bacterial and viral infections, such as influenza or SARS, may be accompanied by symptoms such as fever and chills. ^1.2

An increase in body temperature is part of the body’s defense response to an active infection. ³ The anterior hypothalamus in the brain raises body temperature ⁴ to 38°C or more, producing an effect that we perceive as fever. ⁵

Fever should not be confused with hyperthermia, which occurs when the body produces more heat than it can dissipate. ³ Hyperthermia is most often the result of wearing excess clothing that is inappropriate in hot weather or high humidity, or after strenuous physical activity. ⁴

Chill manifests itself in the form of rapid muscle contraction and relaxation, visually perceived as a shiver. Chills are often observed before the onset of fever. ²

• Questions you can ask your patient

  Ask the patient the following questions: ⁶

  • What are the main and accompanying symptoms?
  • What are the characteristics of these symptoms?
  • What was the treatment for fever and chills?
  • Have you ever had fever and chills?
  • When did the problem occur?
  • What makes fever/chills worse and what makes them less?
  • Do you have other diseases? Are you taking other medications?

• The patient should be referred to a doctor for medical attention in the following cases

  The patient should be referred to a physician immediately if the pharmacy or caregiver observes the following:

  • Paleness; patchy skin lesions; skin, lips or tongue turned blue or ashy
  • No response to social cues
  • Patient has difficulty walking or staying awake
  • Decreased activity
  • Signs of acute respiratory distress syndrome such as nasal flaring, increased respiratory rate, wheezing in the chest, groaning and moderate to severe chest retraction
  • Palpitations
  • Reduced skin turgor
  • Body temperature above 39°C in children aged 3-6 months or body temperature above 38°C in children <3 months of age ⁷
  • Fever with rash
  • Flu-like symptoms that improve but then recur with fever and worse cough ⁸

Etiology

Learn about the causes of fever and chills.

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Treatment

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Fever and Chills

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Causes of severe chills with colds and flu, how to treat this condition

Rinza®

> 9 0007

Colds and flu

>

Severe chills, main causes and treatment

article_cold.png

Severe chills, main causes and treatment

• 7 264

• 7 minutes

Author, editor and medical expert

Elina V. Klimovich

Editor

Harutyunyan Mariam Arutyunovna

Contents:

• Causes
• Why does chills occur without fever?
• How to deal with chills
• Can chills be prevented?
• References

Contents of the article Causes Why does chills appear without fever? What to do with chills Can chills be prevented? References

trembling, in which individual muscle fibers begin to contract, and a goosebumps sensation due to the contraction of the muscles that raise the hairs on the arms and legs. At the same time, a person feels cold, tries to wrap himself in a blanket or curl up. In this way, the body tries to keep warm ^4.5 .

Causes

Chills are most often observed against the background of fever ³ , which accompanies almost all infectious diseases ⁴ is a universal reaction of the organism ⁴ . When microbes and viruses penetrate into it, the body “defends itself” by raising the body temperature ^2.3 .

Since more heat is generated during muscle contractions ⁶ , it means that the more pronounced the chill, the higher the body temperature ² . Light chilling is characteristic of 38 – 39 ⁰ C, “teeth chattering” and severe trembling – for fever in the range of 39 ⁰ – 40 ⁰ C. Terrific chills, covering the whole body, occur at temperatures above 40 ⁰ C ^3.6 .

Chilliness and fever may occur in various infectious diseases, such as colds, influenza ³ or when a focus of purulent inflammation forms in any organ, for example, in the heart, kidneys, pleura, lungs or veins ⁷ . Symptoms are caused by pyrogens, or substances that can affect the thermoregulatory center in the brain. Pyrogens can be biologically active substances released by bacteria, viruses and other pathogens ³ .

Sometimes it is not infectious agents that act as pyrogens, but substances that are formed in the body itself during tissue damage and decay – inflammation, bruises, hemorrhages ^2.3 .

Even if you feel cold, trembling in the body, and the thermometer shows a temperature above 37 ⁰ C, the cause may not be inflammation or even an infection, but the following conditions:

• Nervous strain. With neurocirculatory dystonia (neurosis), chills often begin in the evening or at night. It can be provoked by emotional stress ¹⁶ .
• Hormonal imbalance. Chilling in women on the background of elevated temperature (37-38 ⁰ C) is a common symptom of menopause ^3.7 or premenstrual syndrome ¹⁸ .
• Diseases of the blood. Symptoms resembling infectious fever with shivering may be a sign of hemolytic anemia or lymphoma ¹⁴ .
• Hyperthermia. Overheating of the body occurs after intense physical overstrain, if the ambient temperature is above 26.7 ⁰ C ¹⁴ . Under such conditions, heat transfer is disturbed, and excess heat accumulates in the body ⁵ . Overheating affects athletes participating in competitions in a country with an unusual climate, while not observing the correct drinking regimen, as well as obese people ¹⁴ .

What causes chills without fever?

Chilling can also occur against the background of normal and even low body temperature ^1,2,14 . During hypothermia – for example, during a long stay in the cold or immersion in cold water, ^1.2 – the vessels constrict so that the body does not lose heat. For example, trained swimmers with enough body fat to retain heat typically don’t feel shivering in cold water. But thin people with low levels of physical activity in similar conditions quickly lose blood circulation, develop severe trembling, turning into chills, and body temperature may even drop ¹⁴ .

Other causes of chills without fever include:

• hypoglycemia – low blood glucose – in patients with diabetes ⁹ ;
• hypothyroidism – deficiency of thyroid hormones ¹⁵ ;
• hypertensive crisis – a sharp and significant rise in blood pressure ⁸ .

Shaking without fever may occur if there is a long time between taking antipyretic drugs. These drugs quickly bring down the temperature, but if they are used incorrectly, a side effect sometimes occurs – muscle contraction, that is, trembling in the body. To avoid such phenomena, consult a specialist, he will tell you how to take antipyretics correctly ¹⁴ .

What to do in case of chills

In case of hypothermia, it is enough to warm up – put on warm clothes, drink hot tea or milk ¹ . If the flu or cold against the background of fever (above 38 ⁰ C) and chills, the state of health worsens, the legs and hands become cold, and the skin is “marble”, it is likely that the body temperature will rise, which means that measures need to be taken ^2.10 . First of all, consult a doctor in a clinic or call a doctor at home.

To alleviate unpleasant symptoms, when you feel chills, you should:

1. Wrap yourself in a blanket and keep warm. No need to be afraid that the temperature will start to rise even faster. The body does not lose its ability to resist external heat during fever ² .
2. Wipe the body with warm water at a temperature of 41 ⁰ C and above. Evaporating from the surface of the skin, the water will remove heat and contribute to its gradual cooling. But remember that you can not wipe the skin with cold water: sudden cooling causes even greater muscle and vascular spasm, increases chills and accelerates the rise in temperature ¹⁰ . Antipyretic drug ¹⁰ should be taken 30 minutes before the rubdown.

If you do a rubdown without taking an antipyretic, chills may appear – due to trembling in the body, the temperature will rise again ¹⁷ .

RINZASIP® with vitamin C

To combat fever and other symptoms of colds (ARVI) and flu, paracetamol-based preparations are intended, for example, the combined RINZA® and RINZASIP®, which can be used by adults and adolescents from 15 years of age, and RINZASIP ® for children from 6 years of age ^{11 .12} .

• RINZA® tablets contain paracetamol, phenylephrine, chlorphenamine and caffeine. The drug is ready for action 10 minutes after taking ¹³ , reduces muscle and joint pain, reduces fever ¹¹ . RINZA® also facilitates breathing in case of swelling of the airways, helps to reduce sore throat, itching of the eyes and nose ¹¹ .
• RINZASIP® drink powders with vitamin C contain, in addition to paracetamol, phenylephrine, pheniramine and caffeine, ascorbic acid. RINZASIP® with vitamin C in orange, lemon or blackcurrant flavor reduces cold symptoms and improves body resistance ¹² .

Attention! You can take antipyretic drugs for no more than 5 days ^11.12 . If fever, trembling and coldness persist or recur, a specialist should be consulted to find out the cause of this condition ⁴ .

Can chills be prevented?

To avoid the occurrence of this symptom, it is necessary first of all to act on its causes – to avoid situations in which it occurs, for example, hypothermia or training in conditions of high air temperature ¹⁴ . It is also important to strengthen the immune system and start treating a cold at its first symptoms. If chilliness is not associated with a cold and occurs periodically ^8,14,16 , you should consult a doctor in a timely manner to prevent a new attack. Indeed, in such cases, chills can be a signal that the body gives in various chronic diseases ² .