Merck Manual

Please confirm that you are not located inside the Russian Federation

honeypot link

Common Cold


Brenda L. Tesini

, MD, University of Rochester School of Medicine and Dentistry

Reviewed/Revised Apr 2022 | Modified Sep 2022
Topic Resources
  • Many different viruses cause colds.

  • Usually, colds are spread when a person's hands come in contact with nasal secretions from an infected person.

  • Colds often start with a scratchy or sore throat or discomfort in the nose, followed by sneezing, a runny nose, a cough, and a general feeling of illness.

  • Doctors base the diagnosis on symptoms.

  • Good hygiene, including frequent hand washing, is the best way to prevent colds.

  • Rest, decongestants, acetaminophen, and nonsteroidal anti-inflammatory drugs (NSAIDs, such as ibuprofen) can help relieve symptoms.

Common colds are among the most common illnesses. Many different viruses (rhinoviruses, adenoviruses, coronaviruses, and human metapneumoviruses) cause colds, but rhinoviruses (of which there are more than 100 subtypes) cause most colds. Colds caused by rhinoviruses occur more commonly in the spring and fall. Other viruses cause common coldlike illnesses at other times of the year.

Colds spread mainly when people’s hands come in contact with nasal secretions from an infected person. These secretions contain cold viruses. When people then touch their mouth, nose, or eyes, the viruses gain entry to the body and cause a cold. Less often, colds are spread when people breathe air containing droplets that were coughed or sneezed out by an infected person. A cold is most contagious during the first 1 or 2 days after symptoms develop.

Susceptibility to colds is not increased by any of the following:

  • Becoming chilled

  • General health and eating habits

  • Having an abnormality of the nose or throat (such as enlarged tonsils or adenoids)

Did You Know...

  • Becoming chilled does not cause colds or make people more likely to get a cold.

Symptoms of Common Cold

Cold symptoms start 1 to 3 days after infection. Usually, the first symptom is a scratchy or sore throat or discomfort in the nose. Later, people start sneezing, have a runny nose, and feel mildly ill. Fever is not common, but a mild fever may occur at the beginning of the cold. At first, secretions from the nose are watery and clear and can be annoyingly plentiful, but eventually, they become thicker, opaque, yellow-green, and less plentiful. Many people also develop a mild cough. Symptoms usually disappear in 4 to 10 days, although the cough often lasts into the second week.

Did You Know...

  • Antibiotics are useless in treating colds.

Diagnosis of Common Cold

  • A doctor's evaluation

Doctors are usually able to diagnose a cold based on the typical symptoms. A high fever, severe headache, rash, difficulty breathing, or chest pain suggests that the infection is not a simple cold.

Laboratory tests are not usually needed to diagnose a cold. If complications are suspected, doctors may order blood tests and x-rays.

Prevention of Common Cold

Because so many different viruses cause colds and because each virus changes slightly over time, an effective vaccine has not yet been developed.

The best preventive measure is practicing good hygiene. Because many cold viruses are spread through contact with the secretions of an infected person, the following measures can help:

  • People with cold symptoms and people in their household and workplace should wash their hands frequently.

  • Sneezing and coughing should be done into tissues, which should be carefully disposed of.

  • When possible, people with symptoms should sleep in a separate room.

  • People who are coughing or sneezing because of a cold should not go to work or school where they might infect others.

  • Cleaning shared objects and surfaces with a disinfectant can also help reduce the spread of common cold viruses.

Despite their popularity, echinacea, zinc, and high-dose vitamin C (up to 2,000 milligrams per day) do not prevent or treat colds, nor does eating citrus fruits.

Treatment of Common Cold

  • Rest at home to prevent spread to others

  • Plenty of fluids and inhalation of steam

  • If needed, over-the-counter drugs to relieve symptoms

People with a cold should stay warm and comfortable and should rest. They should try to avoid spreading the infection to others by staying at home. Drinking fluids or using a cool mist humidifier may help a little to keep secretions loose and easier to expel. Vaporizers that release hot steam can cause burns if someone gets too close or accidentally knocks over a device filled with hot water.

Currently available antiviral drugs are not effective against colds. Antibiotics do not help people with colds, even when the nose or cough produces thick or colored mucus.

Several popular nonprescription (over-the-counter) remedies help relieve cold symptoms. Because they do not cure the infection, which usually resolves after a week regardless of treatments tried, doctors feel that their use is optional, depending on how bad the person feels. Several different types of drugs are used:

  • Decongestants, which help open clogged nasal passages

  • Antihistamines, which may help dry a runny nose

  • Nonsteroidal anti-inflammatory drugs (NSAIDs) or acetaminophen, which can relieve aches and pains and reduce fever

  • Cough syrups, which may make coughing easier by thinning secretions and loosening mucus (expectorants) or which may suppress cough (suppressants)

These drugs are most often sold as combinations but can also be obtained individually.

Inhaled decongestants are better than forms taken by mouth for relieving nasal congestion. However, using inhaled forms for more than 3 to 5 days, then stopping, may make congestion worse than it was originally. Ipratropium, a nasal spray available only by prescription, helps dry a runny nose.

Older antihistamines, such as chlorpheniramine, can cause drowsiness. Newer antihistamines, such as loratadine, are less likely to cause drowsiness but are ineffective for treating the common cold.

Decongestants and antihistamines should not be given to children under 4 years old.

NSAIDs, such as aspirin, ibuprofen, and naproxen, can relieve aches and pains and reduce fever, as can acetaminophen. Aspirin is generally not recommended for children because in children, it increases the risk of Reye syndrome Reye Syndrome Reye syndrome is a very rare but life-threatening disorder that causes inflammation and swelling of the brain and impairment and loss of function of the liver. The cause of Reye syndrome is... read more , which is a rare but life-threatening disorder.

Cough suppressants are not routinely recommended because coughing is a good way to clear secretions and debris from the airways during a viral infection. However, a severe cough that interferes with sleep or causes great discomfort can be treated with a cough suppressant.


Drugs Mentioned In This Article

Generic Name Select Brand Names
7T Gummy ES, Acephen, Aceta, Actamin, Adult Pain Relief, Anacin Aspirin Free, Aphen, Apra, Children's Acetaminophen, Children's Pain & Fever , Children's Pain Relief, Comtrex Sore Throat Relief, ED-APAP, ElixSure Fever/Pain, Feverall, Genapap, Genebs, Goody's Back & Body Pain, Infantaire, Infants' Acetaminophen, LIQUID PAIN RELIEF, Little Fevers, Little Remedies Infant Fever + Pain Reliever, Mapap, Mapap Arthritis Pain, Mapap Infants, Mapap Junior, M-PAP, Nortemp, Ofirmev, Pain & Fever , Pain and Fever , PAIN RELIEF , PAIN RELIEF Extra Strength, Panadol, PediaCare Children's Fever Reducer/Pain Reliever, PediaCare Children's Smooth Metls Fever Reducer/Pain Reliever, PediaCare Infant's Fever Reducer/Pain Reliever, Pediaphen, PHARBETOL, Plus PHARMA, Q-Pap, Q-Pap Extra Strength, Silapap, Triaminic Fever Reducer and Pain Reliever, Triaminic Infant Fever Reducer and Pain Reliever, Tylenol, Tylenol 8 Hour, Tylenol 8 Hour Arthritis Pain, Tylenol 8 Hour Muscle Aches & Pain, Tylenol Arthritis Pain, Tylenol Children's, Tylenol Children's Pain+Fever, Tylenol CrushableTablet, Tylenol Extra Strength, Tylenol Infants', Tylenol Infants Pain + Fever, Tylenol Junior Strength, Tylenol Pain + Fever, Tylenol Regular Strength, Tylenol Sore Throat, XS No Aspirin, XS Pain Reliever
Advil, Advil Children's, Advil Children's Fever, Advil Infants', Advil Junior Strength, Advil Migraine, Caldolor, Children's Ibuprofen, ElixSure IB, Genpril , Ibren , IBU, Midol, Midol Cramps and Body Aches, Motrin, Motrin Children's, Motrin IB, Motrin Infants', Motrin Junior Strength, Motrin Migraine Pain, PediaCare Children's Pain Reliever/Fever Reducer IB, PediaCare Infants' Pain Reliever/Fever Reducer IB, Samson-8
No brand name available
Atrovent, Atrovent HFA
AHIST, Aller-Chlor , Allergy , Allergy Relief, Allergy Time , Chlorphen SR, Chlor-Pheniton, ChlorTan, Chlor-Trimeton, Chlor-Trimeton Allergy , Chlor-Trimeton Allergy 12 Hour, Diabetic Tussin Allergy Relief, ED Chlorped Jr., Ed ChlorPed Pediatric, ED-ChlorPed , ED-Chlortan, ED-Chlor-Tan , PediaPhyl , PediaTan, Pediox-S, P-Tann , Qdall AR, TanaHist-PD, Teldrin HBP
Alavert, Allergy Relief, Claritin, Claritin 24 Hour, Claritin Chewable, Claritin Hives Relief, Claritin Liqui-Gel, Claritin RediTab, Clear-Atadine , Dimetapp Children's Non-Drowsy Allergy, QlearQuil All Day & All Night Allergy Relief, Quality Choice Allergy Relief Non-Drowsy, Tavist ND
Anacin Adult Low Strength, Aspergum, Aspir-Low, Aspirtab , Aspir-Trin , Bayer Advanced Aspirin, Bayer Aspirin, Bayer Aspirin Extra Strength, Bayer Aspirin Plus, Bayer Aspirin Regimen, Bayer Children's Aspirin, Bayer Extra Strength, Bayer Extra Strength Plus, Bayer Genuine Aspirin, Bayer Low Dose Aspirin Regimen, Bayer Womens Aspirin , BeneHealth Aspirin, Bufferin, Bufferin Extra Strength, Bufferin Low Dose, DURLAZA, Easprin , Ecotrin, Ecotrin Low Strength, Genacote, Halfprin, MiniPrin, St. Joseph Adult Low Strength, St. Joseph Aspirin, VAZALORE, Zero Order Release Aspirin, ZORprin
Aflaxen, Aleve, Aleve Arthritis, All Day Pain Relief, All Day Relief, Anaprox, Anaprox DS, EC-Naprosyn, Midol Extended Relief, Naprelan, Naprelan Dose Card, Naprosyn
quiz link

Test your knowledge

Take a Quiz!