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Antibiotics in influenza: answers to all questions
Last reviewed: 04.07.2025
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Doctors never tire of repeating that antibiotics are not used for influenza, a disease that has a viral pathogenesis.
Therefore, the question - what antibiotics should be taken for the flu? - is incorrect and can only be asked if the person asking it still does not know the difference between bacteria and viruses. But it is precisely this difference that is the reason why antibiotics are not prescribed for the flu and acute respiratory viral infections.
If you want to know exactly why all doctors recognize contraindications to the use of antibiotics for flu, read on. And then you will be able to ask the right question to the doctor who - in order to be on the safe side in case of possible complications - may prescribe antibiotics to a child with flu. In addition, the local doctor may simply make a mistake in the diagnosis and, without analyzing the symptoms of the respiratory disease, advise taking antibiotics for flu in adults.
[ Antibiotics for flu and acute respiratory viral infections: cuique suum
Indeed, to each his own. Antibacterial drugs do not have a biochemical or physiological effect on viruses, i.e. the pharmacodynamics of antibiotics do not work against flu. And this is despite the fact that antibiotics are able to overcome many types of dangerous pathogenic bacteria due to their ability to change the course of biochemical processes in their cells at the level of membrane damage, cessation of protein synthesis or production of cellular enzymes. By suppressing the growth and reproduction of bacteria in this way, drugs of this group eliminate the source of infection.
But antibiotics are powerless against flu and acute respiratory viral infections: only immunoglobulins and antibodies produced by our body’s immune system, as well as interferons – proteins that activate the immune response in response to attacks by flu, rhinovirus and adenovirus – can kill viruses.
The influenza virus of the genus Influenzavirus A, B and C, which exists in the form of a particle (virion), belongs to the family of orthomyxoviruses (Ortomyxoviridae) - intracellular obligate parasites with an as yet unclear "pedigree". These parasites are fundamentally different from pathogenic and opportunistic bacteria: viruses do not have a cell, but have a protein capsule with RNA fragments, so that viruses can synthesize proteins and reproduce only after settling in the cells of another organism. To replicate, the virus needs a protein from foreign cells, which it "borrows" for its own needs. As virologists note, in the case of influenza, which is spread by airborne droplets, the virus most conveniently "clings" to the epithelial cells of the upper respiratory tract. And the parasite’s adsorption system is superbly developed: on the outer surface of its capsule there are villi consisting of glycoprotein enzymes, which help it penetrate cells almost unhindered and begin reproducing there and producing its own proteins.
Moreover, RNA replication occurs at maximum speed in order to "not get hit" by the immune system, since it reacts to foreign proteins of the virus, which are antigens for the human body. That is why - unlike other respiratory diseases - the first phase of flu is associated with intoxication, the signs of which are manifested by a significant increase in body temperature and chills, weakness and headache, eye pain, muscle pain and aches throughout the body. So, it is, in principle, not difficult to distinguish flu from a cold.
Catarrhal symptoms during influenza also have their own characteristics: dry mucous membrane of the nasopharynx causes a feeling of sore throat, the nose is blocked due to swelling of its mucous membrane, a strong dry cough appears, causing chest pain. But even with these symptoms, even the best antibiotic will not help with influenza.
Antibiotics for flu may be needed in case of complications, such as sinusitis, otitis or pneumonia, which develop due to the activation of opportunistic microbes against the background of weakened body defenses. But this will be antibacterial therapy for the corresponding secondary disease, not for flu.