A cold is germs on the lining of your nose and throat.
Most coughs, colds and sore throats are caused by viruses that settle on the moist lining of the nose, throat and airways. The lining swells and makes mucus to wash them out. They usually clear on their own in about a week, though the cough can linger for up to three.
In plain words.
Antibiotics do not kill viruses, so they do not shorten a cold. Taken when not needed they bring side effects and breed germs that no longer respond. Rest, fluids, warm salt-water gargles and paracetamol ease the worst of it.
Some sore throats are caused by bacteria, usually with fever, swollen tender glands in the neck, white patches on the tonsils, and no cough. These may need an antibiotic.
A cough that lasts more than two weeks needs checking, and in India that includes a test for TB. Other causes of a long cough are asthma, acid reflux, mucus dripping from the back of the nose, smoking, and some BP tablets (such as ramipril or enalapril).
When the infection spreads down into the lungs, as a chest infection or pneumonia, fever and breathing usually get worse after a few days instead of better.
From the nose down to the lungs
Air flows in through the nose, down the throat and windpipe, and into the branches of the lungs. The lining is thin, moist and calm.
Viruses settle in the nose and throat. The lining turns red and swollen and mucus runs; coughing is the body clearing it. The lungs themselves stay clear.
Sometimes the infection spreads down into the lungs. Fever climbs and breathing turns fast and short: that needs a doctor the same day.
Go to hospital now if
- Breathless at rest, unable to finish a sentence, or lips or face turning blue: call 112.
- An oxygen reading (pulse oximeter) below 92 percent at rest: go to hospital now.
- Coughing up more than a streak of blood, or chest pain.
- A very sore throat with drooling, not being able to swallow your own saliva, a muffled voice, or swelling in the neck.
- Confusion or unusual drowsiness.
- Swelling of the lips, tongue or face, especially after a new medicine: call 112.
Call 112 or go to the nearest emergency department. Ambulance: 108 (102 in some states).
See a doctor within a day or two if
- Fever lasts more than three days, or returns after settling
- You get worse after starting to get better, with fever and thick phlegm
- You wheeze, or have asthma, COPD, diabetes, or are over 65
- A sore throat comes with white patches on the tonsils and swollen glands
- A cough has lasted more than two weeks, or you find a streak of blood in the phlegm
Tests that help.
Not everyone needs every test. He decides which ones are worth doing for you.
| Test | What it tells |
|---|---|
| Usually none | A simple cold needs no tests. |
| Pulse oximeter at home | A clip on the finger that reads the oxygen level. Useful when there is breathlessness. |
| Complete blood count (CBC) | When fever is high or lasting. |
| Chest X-ray | When a chest infection is likely, or the cough lasts. |
| Sputum test for TB | A rapid test on phlegm (CBNAAT or TrueNat) for a cough over two weeks. Free at government centres. |
| Flu or COVID test | Only when the result would change what is done. |
Have it ready.
Tick them off as you gather them. The ticks stay on this phone only.
Online, or in person?
Avoid leftover or over-the-counter antibiotics for a cold: they do nothing for a virus and breed germs that no longer respond.
A video call can
- Tell a simple cold from something that needs more
- Look at your throat on camera
- Advise safe relief, and say plainly whether an antibiotic is needed
- Arrange tests for a lingering cough, including for TB
Needs a visit in person
- Listening to the chest, when a chest infection is likely
- A chest X-ray and phlegm tests
- Breathlessness, blue lips or a low oxygen reading: that is an emergency
Talk it through with Dr. Arya.
Bring your reports and medicines to a video consultation. He goes through them with you, in plain words, and says clearly if you need to be seen in person.
Book a video consultationDr. Prabhat Arya · MBBS, MD (Internal Medicine) · Delhi Medical Council Reg. No. DMC-83759