Chills Without Fever: Possible Causes and When to Worry

Evening, you are already under a blanket, but your shoulders still shiver, and the thermometer honestly shows 36.6. Sound familiar? Chills at normal temperature frighten many people, and usually the explanation is simpler than it seems.

What chills are and why they occur without fever

Chills are a sensation of cold caused by spasm of the superficial, skin vessels plus muscle shivering: first the masticatory muscles, then the shoulder girdle, back, limbs, and goosebumps as well. The shivering is not random: by contracting, muscles produce heat, and the body warms up.

The hypothalamus commands the process. A person has a set point of about 37 °C; when it receives a signal that the temperature has deviated from it, thermogenesis is switched on. The signal comes from cold receptors in the skin or from within, from inflammatory substances. This also answers the main question: chills often herald the onset of fever or a rise in temperature, and the thermometer shows normal simply because the temperature has not yet risen.

Chills often occur with hypothermia — here it is a normal protective reaction of a healthy person. It also occurs at the onset of fever in infections, injuries, and other diseases, and chills and a rise in temperature can be caused by some medications. A separate story is chilliness in neuroses: it is only a subjective sensation, and in easily excitable people shivering appears with strong agitation or fright.

What to take from this section: shivering without fever more often indicates that the body is warming up or you are cold. And keep in mind a caveat — a sensation of heat, cold, or chills can occur even at readings below 38 °C, although a temperature is considered elevated from 38 °C.

Causes of chills without fever in women

The causes of chills without fever in women are the same as in men: hypothermia, the onset of an infection, taking certain medications, strong agitation or fright. If the shivering recurs, the doctor clarifies the circumstances — a cold room, agitation before a conversation, a new medication. These details are more useful than the word "chilly."

Why you feel chills at night and during sleep

Chills often precede a rise in temperature, so an episode can also happen at night. At an appointment, the doctor asks how long the episode lasted, whether it was the only one, how often it recurs, and what the maximum temperature was. One night with chills at normal temperature is not a diagnosis; recurring episodes are a reason to discuss them with a doctor.

What examinations help find the cause

First, a conversation: is it only a sensation of cold or true shivering, was there a temperature and what was it, how long do the episodes last, do they recur, did they occur soon after contact with something to which an allergy is possible. Then an examination: skin, eyes, ears, nose, throat, neck, chest, abdomen, measurement of body temperature. Next, the doctor chooses what to check:

• complete blood count with leukocyte differential and urinalysis;
• blood culture;
• sputum culture and urine culture;
• chest X-ray.

The set depends on how long the chills and accompanying symptoms last.

When chills require seeing a doctor

You should not wait if chills are accompanied by neck stiffness, confusion, irritability or lethargy, severe cough, shortness of breath, pain or burning in the abdomen, frequent urination. A separate reason is temperature: when the temperature does not come down and the condition worsens, and the fever does not resolve within three days or persists longer than five.

Chills without fever by themselves are not a reason to call an ambulance; 103 and 112 — if neck stiffness, confusion, or shortness of breath appear, rapidly escalating to a severe condition.

This material is for reference: it suggests what to talk about with a doctor, but does not replace a consultation.

This content is for reference and does not replace a doctor's consultation. Medical disclaimer