Shivering

On its own, shivering could just be a sign that you are feeling cold. Some symptoms of this include:

• Goosebumps (read more: Harvard study solves the mystery of why we get goosebumps)
• Shaking
• Teeth chattering
• You feel better soon after getting into a warm space, warm clothing or having a warm drink

If exposure to extremely cold temperature and shivering continues, it may lead to complications like muscle pain and eventually hypothermia. Remember that different people have different cold intolerance. For example, someone with hypothyroidism is likely to feel cold at higher temperatures than someone who doesn't have this condition. Children and older people might also feel cold and start shivering at warmer temperatures than younger adults.

See a doctor if your shivering doesn't go away even after wearing weather-appropriate clothing or if you have shivering accompanied by any of the following conditions:

• Swelling
• Sweating
• Seizure
• Constipation
• Heart palpitation (arrhythmia)
• Tingling around the mouth
• Muscle weakness
• Muscle pain and stiffness
• Feeling confused (confusion)
• Muscle cramps
• Dizziness
• Fatigue
• Nausea and vomiting

Shivering can be the result of a variety of things. These include:

• Cold environment: When the external temperature drops below the optimum body temperature, you start to shiver. The heat produced in the process keeps the body warm. After a few hours of constant shivering, your muscles start to lose glucose (sugar), which makes them tired and stop shivering.
• After getting an anaesthetic: Anaesthesia is administered during operations. When the effects of the anaesthesia wear off and you regain consciousness, you may start shivering. The reason for this is not well understood. One likely cause is that the operation room is usually cold, so the body temperature starts to decrease and you feel cold because you have been lying down motionless for a long time. Some types of sedation can also tamper with your normal body temperature.
• Reduction in blood sugar levels: Shivering can occur when the blood sugar drops below normal. If you do not eat anything for some time, your blood sugar level may decrease causing shivering. (Read more: First aid for low blood sugar)
• Infection: If you are shivering, but do not feel cold, it may mean that your body is fighting a bacterial or viral infection. As shivering is a process of providing warmth to the body, shivering can increase the body temperature so that the infection causing pathogen dies.
• Adrenaline rush: A rise in adrenaline levels can also lead to shivering. Being scared can cause shivering which is due to the sudden increase in adrenaline levels in the blood.
• Age factors: Risk of shivering increases with old age as the ability to tolerate cold starts decreasing. In addition, many health problems develop with ageing, due to which the ability to tolerate cold is reduced.
  Some children feel cold sooner than adults due to lack of fat in their body. As a result, they begin to shiver quickly.
• Dampness or exposure to cold air: Being exposed to water or air on your skin, you may feel colder which results in shivering in your body.
• Other causes: Anxiety and stress can cause shivering, too.

Extreme cold weather or infection are the most common causes of shivering. You can try some of these precautions to prevent shivering:

• Wear warm clothes in winter.
• Drink warm water and other hot beverages.
• Maintain hygiene to avoid infection, especially during flu season. 
• If you are worried, anxious or stressed use meditation, yoga and other calming techniques. 
• If someone is rendered unconscious for the operation, keep warm blankets, hot water and heaters ready for him/her.

The doctor will ask you questions about your shivering and carry out a physical examination of your skin, eyes, ears, nose, throat andchest. Apart from this, the doctor will also take your body temperature.

Some other tests can also be done during the examination, such as:

• Blood test (complete blood test)
• Blood culture to identify the pathogen in case of an infection
• Mucus test, wherein the mucus extracted from the lungs
• Urine tests (urinalysis)
• Ultrasound
• chest X-ray

The treatment depends on the cause of shivering:

• If the shivering is caused by cold weather or wet skin, dry the skin and cover it with warm clothing. Drink hot tea or coffee to provide warmth to the body.
  Do not use cold water during this time, doing so might intensify shivering. 
• If you are shivering due to an underlying condition, check your body temperature and make sure you do not have a fever. 
• Eating fruits like bananas and grapes, etc., can help correct low blood sugar (hypoglycemia). If you are not able to keep your blood sugar normal, eating sweet candy can be quite beneficial. If your blood sugar decreases frequently, keep a snack with you.
• Keeping some blankets around before an operation can help keep your body warm after the operation.