What are the dangerous side effects of antibiotics?

Antibiotics are highly effective drugs that help to cope with the most difficult and dangerous infections of a bacterial nature. Antimicrobial drugs can quickly eliminate bacterial inflammation and reduce the risk of complications. However, the use of potent antibiotics is almost always accompanied by a manifestation of side effects of varying severity. Some of them disappear after drug withdrawal, while others require thorough treatment.

Table of contents:

  1. Why do medications harm the organism?
  2. What side effects can antibiotics cause?
    1. Stomatitis after antibiotics
    2. What does the appearance of a raid on the tongue mean?
    3. Superinfection
    4. Why does hair start to fall out?
    5. Digestive disorder
    6. Discharge in women after taking antibiotics
    7. What are allergic manifestations?
    8. How do antibiotics affect the liver and kidneys?
    9. What is the effect of drugs on the nervous system?
    10. How can antibiotics harm blood?
    11. The danger of endotoxic shock
  3. Conclusion
  4. Useful links

Why do medications harm the organism?

Taking medicines can not only cure the patient but also harm his health due to side effects. They occur due to the diverse toxic effects of antibiotics on the body. The degree of severity and reversibility directly depends on both the patient’s state of health and the characteristics of the pharmacodynamics and pharmacokinetics of the drug.

There are many different groups, or classes, of antibiotics. These classes have side effects and typically affect men and women the same way. However, certain side effects are more common from some antibiotics than from others [1].

The following disorders most often develop:

  • Dyspepsia and intestinal dysbacteriosis are various digestive disorders associated with the negative effect of antibiotics on the internal organs and intestinal microflora (for example, constipation or diarrhea after antibiotics, nausea, vomiting, abdominal pain, loss of appetite, etc.).
  • Violations of the nervous activity due to the toxic effects of antibiotics on the central nervous system.
  • Allergic reactions are the logical outcome of hypersensitivity to the components of antibiotics. The severity ranges from small skin rashes to life-threatening anaphylactic shock.
  • Superinfection is a rarer occurrence due to a change in the balance of the natural microflora and a decrease in immunity.
  • Thrush usually develops due to increased reproduction of Candida fungi.

What side effects can antibiotics cause?

The side effects of antibiotics are very diverse. Sometimes even an experienced doctor is not able to predict how the patient’s body will react to this or that medicine. As a rule, people who are sick rarely and have strong immunity, much less likely to complain of side effects.

If the defenses are weakened, especially by the frequent use of antibiotics, the reaction can be very strong. The risk group also includes children whose immune system is not yet fully developed. It also includes the elderly, as well as people having a chronic illness in history. What are the consequences of antibiotic therapy?

Stomatitis after antibiotics

This disease is an inflammation of the mucous membranes of the oral cavity with the development of redness, swelling and the appearance of ulcers. Antibacterial agents, especially long-taken, change the composition of the natural microflora in the mouth. They negatively affect the state of the immune system. As a result, the mucosa becomes very vulnerable to various pathogens such as fungi, viruses, and bacteria. They do not meet obstacles and begin to actively proliferate, causing inflammation and ulceration. This side effect is especially common in young children.

Stomatitis after antibiotics

The disease is accompanied by severe pain in the process of talking or eating, itching and burning, less often – an increase in temperature. This condition requires immediate treatment in the form of fungicidal, antibacterial or antiviral agents. In addition, experts prescribe symptomatic therapy to reduce swelling and pain. Only the attending physician can choose the right antibiotics. Self-medication, in this case, will only aggravate the condition.

What does the appearance of a raid on the tongue mean?

As you know, the state of this organ often allows you to judge any violations in the body. Normally, it is pink, moist, without cracks, but the following changes can cause pathological processes:

  1. White tongue after taking antibiotics indicates an imbalance of the natural microflora and reproduction of the Candida fungus. Candidosis of the oral cavity is accompanied by itching and burning. When you try to remove whitish deposits mechanically, the mucous bleeds. The treatment, in this case, is carried out with the help of fungicidal preparations taken by mouth, vitamins, and treatment of the mouth with antiseptics.
  2. Brown tongue after consuming antibiotics indicates dysfunction of the liver or the digestive system as a whole. The bloom of this color is a consequence of hepatitis, cholecystitis, peptic ulcer, colitis, and dysbiosis. Running candidiasis can also cause darkening. The attending physician prescribes treatment in accordance with the analyzes and the results of the medical examination.
  3. The red tongue is a sign of an allergic reaction. In this case, it is often accompanied by other characteristic external manifestations (rash on the skin, swelling, itching). Eliminated by the abolition of the drug or replace it with a less toxic. It is worth remembering that only a specialist will be able to reliably determine the cause of the phenomenon and prescribe the appropriate therapy.



Superinfection after antibiotics is quite common, since the drug used destroys microorganisms indiscriminately, disrupting the microflora balance. As a result, some groups of pathogens that are not susceptible to the medication used and are not restrained by the more beneficial symbiotic bacteria begin to actively proliferate. In this case, there is endogenous superinfection (such as candidiasis).

If the body is weakened by therapy, it is attacked from the outside, we are talking about exogenous superinfection. The treatment is carried out in accordance with the results of microbial culture using antimicrobial agents appropriate to the diagnosis.

Why does hair start to fall out?

It should be borne in mind that antibiotics do not directly affect the condition of the hair. However, cases of alopecia with or after therapy are sometimes recorded. This allows you to judge the presence of indirect communication. Indirect causes of hair loss can be the following symptoms:

  • general stress state of the body during the period of illness. This is not only characteristic of bacterial infections
  • dysbacteriosis and associated vitamin deficiency and reduced immunity. As a result, the hair follicles do not receive sufficient nutrition and die
  • impaired absorption of vitamins minerals in the intestine due to dysbiosis
  • superinfection (eg, fungal), which affects the scalp in women, men and children

Supportive therapy can help prevent baldness with antibiotic treatment. Doctors recommend taking vitamin complexes since dysbiosis leads to a deficiency of the B-group vitamins synthesized in the intestine, as well as pre- and probiotics.

Digestive disorder

One of the most common side effects of taking antibiotics is antibiotic-associated diarrhea. With a severe course, severe diarrhea may develop up to 10-15 times a day.

In addition, constipation may occur. If you follow the appropriate diet and receive probiotics, it passes quickly. However, if the defecation is still difficult 5–7 days after completion of treatment, serious complications are likely after taking antibiotics. This condition requires a visit to a doctor to diagnose the cause and take appropriate measures. Proper nutrition, both during and after treatment, will help prevent digestive problems and prevent constipation.

The diet should consist mainly of vegetables, fruits, dairy products, lean meat. Heavy fried, salty and spicy foods, as well as sources of fast carbohydrates, should be temporarily excluded. Experts recommend drinking plenty of liquids.

Discharge in women after taking antibiotics

Women often complain of the appearance of various discharges after taking the medicine. This side effect of antibiotics is caused by dysbacteriosis, which affects not only the intestines but also the vagina. Most often, antimicrobial agents of a wide range provoke candidiasis, accompanied by discomfort in the genital area and characteristic cheesy secretions of white color. In this case, the gynecologist prescribes oral formulations or suppositories (tablets) for topical use.

Other pathogens can be more rarely activated. Perhaps the development of colitis, gardneurlosis, ureaplasmosis, and another vaginitis. If, after taking antibiotics, there are any pathological secretions of an unusual color (they are normally transparent), with an unpleasant smell or without it, then the woman should immediately contact a gynecologist. The doctor will prescribe a bacteriological examination and appropriate treatment.

What are allergic manifestations?

Side effects in the form of an allergic reaction may occur on antibiotics of any group. This effect is due to personal intolerance to the components of antibiotics. In this case, the drug acts as an antigen (foreign substance), in response to which the immune system produces protein complexes called antibodies.

Most often, an allergy occurs to penicillins and cephalosporins. Given the similarity in the structure of these antibiotics, replacing one with another is prohibited, since there is a chance of a cross-reaction.

Allergy symptoms can be local and generalized:

  • Allergic rashes, burning skin, itching, scratching
  • Asthmatic bronchitis
  • Quincke’s edema
  • Urticaria
  • Anaphylactic shock
  • Stephen Jones syndrome (toxic necrolysis of skin cells)

Such side effects after taking antibiotics can cause irreparable harm to human health. In rare cases, an antibiotic can cause a severe and potentially life-threatening allergic reaction known as anaphylaxis. Initial symptoms of anaphylaxis are often the same as a mild allergic reaction [2].

Therefore, the attending physician should conduct history of the disease and the allergic status of the patient. The test for a specific type of antibiotic is desirable. If complications have occurred at home, then the patient should immediately call the ambulance.

How do antibiotics affect the liver and kidneys?

harmful effects of antibiotics on the liver

Manifestations of nephrotoxicity and hepatotoxicity usually occur in individuals who already have lesions of the liver and kidneys. Especially such side effects occur in people suffering from glomerulonephritis, pyelonephritis, hepatitis of varying severity and etiology, hepatosis. Symptoms of deterioration are:

  1. Darkening of the urine, lightening feces, discoloration of the skin (yellowness), yellowing of the sclera, hyperthermia develop due to the toxic effect of antibiotics on the liver. In the biochemical analysis of blood, liver markers change.
  2. Decrease/increase in the volume of urine excreted, painful sensations in the lumbar region, the occurrence of irrepressible thirst, possibly an increase in body temperature due to the toxic effect of antibiotics on the kidneys. The level of urea or creatinine increases in the blood test. In the general analysis of urine, doctors observe an increase in density, the appearance of salts, protein, glucose, erythrocytes, and leukocytes.

Before using the antibiotics, the patient must undergo a specialist examination. In addition, he must inform the specialists about the already existing chronic diseases. The doctor will be able to select the necessary therapeutic dose and prescribe the duration of treatment, taking into account pathologies.

The following antibiotic groups have a hepatotoxic and nephrotoxic effect:

  • Tetracyclines
  • Erythromycin
  • Rifampicin
  • Sulfonamides

Experts recommend the joint appointment of hepatoprotectors and nephroprotectors. This is especially true for individuals who take a long-term antibiotic, for example, in the treatment of tuberculosis infection.

What is the effect of drugs on the nervous system?

The tetracycline and aminoglycosides group of antibiotics have the greatest neurotoxicity. They are able to affect the myelin sheath of nerve fibers. With a short course of treatment, headaches, dizziness, heaviness in the occipital and temporal regions may occur. Symptoms of significant toxic effects of antibiotics are:

  • Dysfunction of the visual, auditory pathways, which leads to partial or complete loss of vision and hearing
  • Vestibulopathy – impaired coordination, a tendency to motion sickness, a manifestation of motion sickness
  • Toxic damage to kidney innervation
  • Development of generalized polyneuropathy

The purpose of such groups of drugs is prohibited in childhood because serious complications that can be fatal occur.

How can antibiotics harm blood?

Long-term use of chloramphenicol leads to impaired rheological properties of blood. In addition, severe anemia may develop.

  1. Hemolytic anemia is a pathological condition in which blood cells are destroyed due to the sedimentation of drug metabolites on them.
  2. Aplastic anemia. It develops against the background of the influence of active substances on the sprouts of the red bone marrow.

With the inevitable appointment of chloramphenicol, the control of blood tests in the dynamics of the disease is mandatory.

The danger of endotoxic shock

Endotoxic shock develops when taking bactericidal agents. Poisoning by toxins occurs in the body as a result of the destruction of pathogenic bacteria. This is a common complication in the treatment of meningitis, meningococcal infection, typhoid fever, and leptospirosis.

Sometimes side effects from antibiotics develop with the wrong method of administration or non-compliance with the rules of asepsis. Intramuscular injection may be complicated by painful infiltration, abscess, and intravenous by phlebitis. After ingestion may occur inflammation of the mucous membrane of the stomach, duodenum. A local antibiotic may cause dermatitis or inflammation of the conjunctiva.


There may be other side effects of antibiotics as a response to different body systems. Often, patients complain of headaches, sleep problems, nervousness, depression. This is due to the negative effects of antibiotics on the nervous system. Especially dangerous are ototoxic drugs, which negatively affect the vestibular apparatus and the auditory nerves.

Pregnant women should not forget about the teratogenic effects of some antibiotics on the fetus. This requires a particularly cautious approach to the treatment of bacterial infections. When using fluoroquinolones, damage to the connective tissue (tendons) is likely. The doctor must also take it into account when prescribing this medication.

Sometimes antimicrobials are powerless against infection. With what it can be connected? There are several likely reasons, and each requires separate consideration:

  1. Resistance is the immunity of a pathogen to antibiotics. It is associated with the wrong selection of the drug, and with the formation of addiction. That is, with frequent use of the same drug, pathogens become resistant. To cure such an infection, you will need to make backpox to identify a particular strain.
  2. Self-medication is the most common cause because, without special education and access to diagnostic tools, it is impossible to choose the right medicine. In addition to the lack of a therapeutic effect, such independence is fraught with superinfections and complications.

Today, a person can not do without the use of antibiotics. However, you can reduce the risk of the harmful effects of their side effects on the body. To do this, you need to consult a competent doctor for advice. The patient should not self-medicate. The patient must strictly follow the instructions. A healthy lifestyle and diet during the period of antibiotic therapy are also important. In addition, probiotics, special preparations of living lactic and bifidobacteria, will help support the body.

Useful links

[1] Follow the link https://www.healthline.com/health/infection/antibiotic-side-effects to know additional information about the side effects of antibiotics.

[2] Read more facts about antibiotics on the site https://www.nhs.uk/conditions/antibiotics/side-effects/

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