Chills are your body’s way of generating heat, and treating them depends on what’s causing them. Most often, chills accompany a fever as your brain temporarily raises your body’s target temperature, triggering rapid muscle contractions to close the gap. The good news: most chills can be managed at home with warmth, fluids, and basic over-the-counter medication.
Why Your Body Produces Chills
A region of the brain called the hypothalamus acts as your internal thermostat. When you’re fighting an infection, inflammatory signals tell the hypothalamus to raise your set-point temperature, sometimes by several degrees. Your body now perceives its normal temperature as “too cold,” so it activates skeletal muscles to contract rapidly. That involuntary shivering is what you feel as chills, and it’s remarkably effective at producing heat quickly.
This is why chills typically hit before or at the beginning of a fever, not after. Once your body temperature catches up to the new set point, the shivering stops and you feel hot instead. Understanding this cycle matters because it shapes how you should respond: fighting the chill with warmth is working with your body, not against it.
Warm Up Strategically
The single most effective thing you can do during a chill is apply warmth. Research on warming strategies shows that active warming (warm blankets, heated air) can reduce shivering by 60 to 80 percent compared to no intervention. While those numbers come from surgical settings, the underlying physiology is the same: external heat reduces the gap between your current body temperature and the target your brain has set, so your muscles don’t have to work as hard.
At home, that means layering blankets, wearing warm socks, and using a heating pad on a low setting if you have one. Warm liquids like tea, broth, or heated water with honey serve double duty: they deliver heat from the inside and help with hydration, which your body burns through faster during a fever. Avoid ice-cold drinks, which can intensify shivering.
One thing to watch for: once the fever breaks and you start sweating, peel back the layers. Trapping too much heat at that point can make you uncomfortable and delay your body’s natural cool-down.
Use Over-the-Counter Fever Reducers
Because chills are driven by fever, bringing your temperature down will usually stop them. Acetaminophen and ibuprofen are the two standard options. Both lower the set point in your hypothalamus, which removes the signal that triggers shivering.
For adults, the key safety limit to remember with acetaminophen is 4,000 milligrams in 24 hours. Going over that threshold risks serious liver damage, especially if you’re taking combination products (cold medicines, sleep aids) that also contain acetaminophen. Check labels carefully. Ibuprofen should be taken with food to protect your stomach, and people with kidney issues or a history of stomach ulcers should stick with acetaminophen or check with a pharmacist first.
These medications typically start working within 30 to 60 minutes. If chills return as the dose wears off, you can take another dose following the timing on the label. Alternating between acetaminophen and ibuprofen is a common approach, but keep a written log of what you took and when so you don’t accidentally double up.
Stay Hydrated
Fever increases fluid loss through sweat and faster breathing, even when you don’t notice it. Dehydration makes chills worse and slows recovery. Water is fine, but drinks with some electrolytes (sports drinks, diluted juice, broth) are better if you’ve been feverish for more than a few hours or haven’t been eating much. Aim for small, frequent sips rather than forcing large amounts at once, especially if nausea is part of the picture.
Chills Without Fever
Not all chills come with a fever. Cold exposure, low blood sugar, intense anxiety, and certain thyroid conditions can all trigger shivering. If you’re chilled but your temperature reads normal, think about context. Did you skip a meal? Are you stressed? Have you been in a cold environment? These causes usually resolve on their own once you warm up, eat something, or calm down.
Persistent chills without fever that show up repeatedly or without an obvious explanation are worth investigating. Anemia, underactive thyroid, and certain hormonal shifts (including menopause) can all make you more prone to feeling cold. A basic blood panel can usually identify or rule out these causes.
Mild Chills vs. Shaking Chills
There’s a meaningful difference between feeling chilly and experiencing violent, teeth-chattering shaking. Intense shaking chills, sometimes called rigors, are a stronger immune response and can signal a more serious infection. Research published in the British Journal of General Practice found that shaking chills had a 90% specificity for bacterial infection in the bloodstream, compared to just 52% for mild chills. In practical terms, that means if you’re shaking uncontrollably rather than just feeling cold, your body may be fighting something that needs medical attention.
When Chills Need Medical Attention
Most chills resolve within a day or two as the underlying illness runs its course. But certain combinations of symptoms signal something more urgent. For adults, the Mayo Clinic flags these as reasons to seek care promptly: a fever of 103°F (39.4°C) or higher, trouble breathing, chest pain, severe headache, stiff neck, or confusion.
For children, the thresholds are lower and the stakes higher. Fever is generally defined as a core temperature of 100.4°F (38°C) or above, and any infant under three months with a fever needs immediate evaluation. In older children, watch for pale or mottled skin, reduced activity, poor feeding, a weak or high-pitched cry, or fast breathing. The presence of rigors in children is associated with roughly twice the likelihood of a serious bacterial infection compared to children without rigors (15% vs. 6%), so shaking chills in a child should prompt a call to your pediatrician rather than a wait-and-see approach.
Chills that come and go over several days without improvement, chills that develop after recent surgery or a medical procedure, and chills in anyone with a weakened immune system all warrant a medical evaluation sooner rather than later.