Chills
Chills are episodes of shivering, cold sensation, and goosebumps, often arriving as body temperature rises with infection, though they can also occur without a fever.
Overview
Chills are the familiar sensation of feeling cold, shivering, and sometimes shaking, often paired with goosebumps and a desire to bundle up even in a warm room. Many people first notice chills at the start of an illness, where the cold feeling and trembling can precede a measurable fever by minutes or hours. The experience can range from a mild, passing shiver to intense, teeth-chattering shaking that is hard to control.
Although chills are most strongly associated with fevers and infections, they are not always a sign of illness. Cold exposure, strong emotion, and certain other situations can produce the same shivering response. What makes chills informative is the company they keep: whether they arrive with fever, sweats, body aches, or other symptoms, and how intense and persistent the episodes are. As a stand-alone sensation, chills are best read as a clue rather than a diagnosis.
What it is
Shivering is the body's way of generating heat. Muscles contract and relax rapidly, producing warmth as a by-product, while the small muscles at the base of body hairs tighten to create goosebumps and reduce heat loss. This response is coordinated by the hypothalamus, the brain region that regulates body temperature. When the hypothalamus raises the body's internal set point — as it does during many infections — the body suddenly perceives itself as too cold and triggers shivering to climb toward the new, higher target.
This explains the close relationship between chills and fever. Chills frequently mark the rising phase of a Fever, as the body works to reach a higher temperature; once that target is met, the cold feeling typically eases and may be followed by warmth and sweating. A brief shivering episode can also accompany a Mild fever during a routine viral illness, or the more pronounced, shaking chills that some people describe with the Flu. Chills without any fever, by contrast, often trace back to cold surroundings or other non-infectious triggers.
Commonly discussed drivers
The most commonly discussed driver of chills is infection. Viral illnesses such as colds and influenza, as well as bacterial infections including urinary tract infections, pneumonia, and strep throat, frequently produce chills as the body mounts a fever response. Especially intense, shaking chills — sometimes called rigors — are often discussed in the context of more significant bacterial infections, and they tend to prompt closer attention.
Not all chills come from illness. Simple cold exposure, getting wet, or a sudden drop in surrounding temperature can cause shivering as a normal protective response. Strong emotional reactions, intense physical exertion followed by cooling, and reactions during certain treatments are also mentioned. Less commonly, recurring chills can be linked with conditions such as thyroid imbalance, low blood sugar, or other systemic issues. As with fever, the surrounding pattern and accompanying symptoms usually carry more meaning than the shivering on its own.
Conventional context
In conventional care, chills are interpreted largely through the lens of whether a fever or infection is present. Clinicians ask when the chills began, how intense they are, whether they come in distinct episodes, and what other symptoms accompany them. Shaking chills that arrive alongside a high fever can be a useful signal, sometimes pointing toward a bacterial infection that deserves prompt evaluation. The history and examination guide whether testing — such as urine, blood, or imaging studies — is warranted.
Because chills are usually a feature of an underlying process rather than a problem to address directly, conventional management focuses on the cause. Comfort-oriented discussion typically centers on warmth, rest, and fluids, along with the same over-the-counter antipyretic categories people use for fever when discomfort is significant. As with fever, the emphasis is on the person's overall condition and the source of the illness rather than on suppressing the shivering itself.
Complementary & traditional approaches (educational)
Traditional approaches to chills tend to emphasize warmth and comfort while the body works through the rising phase of a fever. Warm blankets, warm fluids, and rest are the measures most commonly mentioned, alongside the simple step of keeping the surroundings comfortable. These ideas are framed here for education only and are not treatments; persistent or severe chills with fever still merit appropriate evaluation.
Several warming botanicals appear in folk traditions connected with feverish, shivery illness. Ginger is widely referenced for its warming quality and its use in soothing teas, Cinnamon appears in many warming traditional preparations, and Elderberry is commonly discussed during colds and flu-like illness. Evidence varies considerably by ingredient and outcome, and individual responses differ. These comfort-oriented traditions are best understood as ways to feel more at ease during a self-limited illness rather than as substitutes for care when warning signs are present.
Safety & cautions
Chills warrant more caution in certain situations. Intense, uncontrollable shaking chills paired with a high fever can signal a more serious infection and deserve attention rather than watchful waiting. Chills in newborns and very young infants, older adults, people who are pregnant, and those with weakened immune systems or chronic illnesses carry more weight, since infection in these groups can progress less predictably.
Particular care is warranted when chills accompany features such as a stiff neck, confusion, difficulty breathing, chest pain, a rash that does not fade under pressure, persistent vomiting, or signs of dehydration. Chills that follow recent travel to areas with specific infectious risks, or that recur without a clear explanation, are also worth taking seriously. As a general rule, the more unwell a person appears and the more warning signs that travel with the chills, the lower the threshold for seeking help should be.
When to seek medical care
Medical assessment is commonly advised when chills accompany a high or persistent fever, when shaking chills are intense, or when chills appear in an infant, older adult, pregnant person, or someone with a weakened immune system. Evaluation is warranted if chills travel with a stiff neck, severe headache, confusion, difficulty breathing, chest pain, a non-fading rash, persistent vomiting, or signs of significant dehydration.
For an infant under three months, any fever or marked chills are generally treated as urgent. Chills following recent travel to regions where infections such as malaria are a concern also call for timely evaluation, as do recurring chills without an obvious cause. When chills are brief, clearly tied to cold exposure or a recognizable mild viral illness, and the person is otherwise doing well, supportive warmth and monitoring are often appropriate, with a low threshold to seek care if symptoms intensify.
FAQs
Why do chills often come before a fever?
When the body raises its internal temperature set point during infection, it suddenly perceives itself as too cold and triggers shivering to generate heat and climb toward the new target. This is why the cold, shivery feeling often arrives just before the temperature reading rises.
Can you have chills without a fever?
Yes. Cold exposure, getting wet, strong emotion, and intense exertion can all produce shivering without any fever. Some non-infectious conditions can also cause chills, so the surrounding context helps clarify the cause.
What are shaking chills, or rigors?
Rigors are intense, uncontrollable episodes of shaking and teeth-chattering, often paired with a sharply rising high fever. They are frequently discussed in the context of more significant bacterial infections and generally warrant prompt evaluation.
When should chills prompt a visit to a clinician?
Chills with a high or persistent fever, intense shaking chills, or chills paired with a stiff neck, confusion, breathing difficulty, or a non-fading rash all warrant attention. Chills in infants, older adults, pregnant people, or those with weakened immune systems, and chills after travel to higher-risk regions, also deserve timely evaluation.