Expert corner

Autor: Katarina Fehir Šola

mag. pharm, univ. mag. pharm


Flu or cold? What are the main differences?

Flu and cold are not the same, although people often confuse them and they are the most common reason for visiting a pharmacy. What are the main differences?


Symptoms and signs Flu Cold
Occurrence (onset of disease) very abruptly gradually
Temperature high normal or moderately elevated
Headache normally rarely
Muscle pain often rarely
Fatigue and exhaustion more pronounced no
Cough dry, very unpleasant none or mild
Nasal congestion sometimes normally
Sneezing  sometimes commonly
Complications often very rarely
Absence from work and school often rarely


The common cold

The common cold is the leading reason to see a doctor. Cold is an upper respiratory infection that is caused by viruses and is highly contagious. The cold is usually mild, lasts for about three days, and can last up to ten days. We can say that the common cold is actually rhinitis with a pronounced throat inflammation. The most common causes of the common cold are rhinoviruses and coronaviruses. The disease is manifested without fever and general symptoms. The treatment is symptomatic. In most of the cases (75%) the upper respiratory tract infections are of viral origin and tend to spontaneously pass after about a week. However, despite this fact, these infections are the most common reason for prescribing antibiotics in medical practice. They are the cause for their irrational use and developing resistance to them. 

There are more than 200 viruses known to cause cold symptoms. The most common are rhinoviruses, coronaviruses, adenoviruses, coxsackieviruses, echoviruses, orthomyxoviruses (including influenza A and B viruses), paramyxoviruses, respiratory syncytial virus and enteroviruses. Colds most often occur during the fall and winter, that is, at the beginning of the school year and with the occurrence of unstable and changeable weather. 

Most often, children get sick, especially if they are in contact with other children in school or kindergarten. Children have a cold about six to ten times a year. In families with school children, the number of colds per child can be as high as 12 on a yearly basis. Adults have a cold about two to four times a year, although this varies greatly from one person to another.

Cold symptoms begin 1 to 2 days after being exposed to a cold-causing virus. The symptoms of a cold are:

  • sneezing, sore throat and cough, lacrimation
  • watery nasal secretion (runny nose)
  • nasal congestion and difficulty with nasal breathing 
  • headache, smell disorder
  • elevated temperature up to a maximum of 38°C

Cold symptoms can last from 2 to 14 days. If the symptoms occur frequently or last much longer than two weeks, they may be more likely a consequence of an allergy than a cold. Allergy and cold symptoms are often confused because they are similar (no elevated temperature occur in case of allergies). And if the temperature rises to more than 38°C accompanied by with shivering and sweating, muscle pain in the arms and legs, and if you feel fatigue and general weakness, it might be flu.

Sometimes a cold can lead to bacterial infections of the middle ear (especially in children) or sinuses, as well as pneumonia, which requires antibiotic treatment (prescribed by a medical doctor). High fever with chills or shivering, severe cough with purulent sputum, severely swollen glands, severe facial pain in the sinus area, may indicate a complication or more serious illness that requires a doctor’s help.



Flu occurs very rapidly, accompanied by elevated temperature and more pronounced symptoms. The temperature can be extremely high (higher than 40 ° C) and is accompanied by shivering. Flu is a serious acute illness of the respiratory system. Symptoms are much more severe than in the common cold, where headaches, muscle aches, a feeling of powerlessness and fatigue can occur. High temperatures can last up to seven days. In addition to these symptoms, respiratory symptoms, irritable cough, laryngitis, conjunctivitis may occur. Complications threatening the patient’s life can occur. Recovery is relatively long and slow. It has a seasonal appearance, most often in winter. The disease has frequent and numerous complications. We only treat complications with antibiotics.


Basic influenza treatment is symptomatic and indicates procedures for eliminating and alleviating certain symptoms of the disease if they are more pronounced. It involves resting, fluid compensation (or infusion in more severe forms of the disease), and taking medications to lower fever and calm coughs. Since the flu is caused by viruses, antibiotics are not efficient, so they can only treat bacterial complications, that is, ear infections, sinusitis and pneumonia. Antiviral medicines are also used to treat the flu, as recommended by a medical doctor, which are taken within the first 48 hours after the onset of the disease. They significantly reduce the duration of the disease and reduce the severity of the symptoms, and in a high percentage reduce the number and severity of complications. 

Self-medications used for symptomatic treatment are analgesics, antipyretics, nasal drops, antihistamines, cough preparations (dry and productive). Paracetamol, ibuprofen, naproxen and acetylsalicylic acid are used for pains and fever.

Combinations of medicinal substances have anti-inflammatory and analgesic effects are used for the treatment of sore throat. 

If you use decongestant nasal drops, do not do this for longer than 3 to 5 days! It is recommended that seawater products that moisturize and protect the mucous membranes of the nose and promote decongestant activity should be used in addition to the nasal decongestant drops.

It is certainly desirable, if the body is weakened, to take vitamins and minerals that support the body’s defense mechanism (vitamin C, zinc, echinacea, propolis, royal jelly, etc.). You need to consult your pharmacist about the proper choice of the preparation.

In non-complicated cases, only symptomatic treatment is available:

  • Resting in bed, taking warm liquids and water 
  • Vitamin C and the administration of some medicines that relieve the symptoms of cold and flu
  • Wearing lighter clothing in case of high temperature
  • Taking sufficient amounts of liquid

Antibiotics do not kill viruses!  They should only be used for rare bacterial complications such as sinusitis or ear infections, which develop as secondary infections. The use of antibiotics “just in case” will not prevent secondary bacterial infections. Follow the physician’s and pharmacist’s advice.

How can flu and cold be prevented?

Washing your hands and wearing face masks is the simplest and most effective way to prevent rhinovirus cold. The other way is to avoid touching the nose or eyes. People who have a cold should always sneeze or cough in a tissue paper and then throw it away. Close, long-term contacts with people having cold should be avoided if possible. Since rhinoviruses can survive for up to three hours outside of the nasal passages on objects and skin, cleaning the surfaces with a virus-killing disinfectant could help prevent the spread of the infection. The room where you are staying should be regularly ventilated. The area can also be refreshed with essential oils that have antibacterial activity.

Since flu is a serious illness, and it can be extremely severe for the elderly and chronic patients, and since it appears epidemically, it is important to undertake preventive measures. The only effective treatment for influenza prevention is active immunization, that is, vaccination.