Treatments & Therapies

Chemoprophylaxis – treatment, effect and risks


If chemoprophylaxis is induced, the physicians administer a virustatic or an antibiotic to the patient in order to treat a detected or impending infection prophylactically (preventively). The purpose of dispensing these drugs is to prevent or combat the spread of the pathogens in the body.

What is chemoprophylaxis?

Various forms of prophylaxis are available to physicians: according to microorganism, time of use and indication. Chemoprophylaxis includes medicinal protective measures in the form of tablets or vaccinations . These treat an existing infection or prevent it if the pathogens have not yet spread in the human organism.

The drugs kill the pathogens in the blood , provided the patient has no resistance to the substance used. Tablets cannot prevent some types of infection, such as malaria , but they can kill the pathogens. 

With the increasing number of pathogen resistances, a residual risk remains for some infectious diseases, since there is no complete medicinal protection. The allocation of the right medication depends on the patient’s individual factors such as state of health, age, previous illnesses, resistance and any existing allergies to individual components of the substances.

Function, effect & goals

If the indication is based on a microorganism, the doctor administers antibacterial and antiviral chemoprophylaxis. By time of use: With pre-exposure prophylaxis, patients suffering from HIV infection take antiviral medication to avoid a risk situation, e.g. B. unprotected sexual intercourse , to eliminate or at least minimize. 

Post-exposure prophylaxis (PEP) is administered to patients in the presence of contamination with pathogens to prevent further spread in the organism.

Such an infection can occur, for example, in the hospital through contact with insufficiently sterile equipment such as a syringe. In addition, transmission of the infectious disease to other people must be prevented. This type of prophylaxis takes the form of anti-viral drugs or antibiotics.

 Vaccination is also possible if the patient is at risk of rabies from an animal bite . In the case of surgical interventions and operations, perioperative chemoprophylaxis prevents inflammation of larger wound areas and the infiltration of pathogens (germs, bacteria) into the bloodstream. 

Malaria prophylaxis is carried out at the time of indication in order to prevent infection with the malaria infection. Exposure prophylaxis protects against transmission of disease by insects. The stand-by prophylaxis develops a long-term effect.

Patients who repeatedly suffer from recurrent urinary tract infections are treated with antibiotics. Chemoprophylaxis is used for various diseases and pathogens: tuberculosis , malaria, meningitis , pertussis (whooping cough) and meningococci .

 Meningococcal disease (Neisseria meningitidis) occurs when the pathogen settles in the nasopharynx. people with a healthy immune systemshow no clinical symptoms when these pathogens are present. The body is able to break down these pathogens on its own.

The pathogens die off rapidly outside the focus of infection, therefore very close interpersonal contact and transmission of oropharyngeal secretions are necessary for transmission and contamination. The disease progresses in the form of meningitis and is usually characterized by sepsis.

In particularly severe cases, septic shock can occur. Headaches , chills , fever and a severe feeling of illness are the accompanying symptoms. The mortality rate is particularly high among infants, young children and the elderly. Meningitis can lead to irreversible brain damage. 

Severe cases of septic disease can cause permanent disability, limited necrosis , and extensive limb gangrene. Meningitis can cause cerebral palsy, seizures , hemiplegia, damage to the inner ear , deafness , intellectual disabilities, andcause hydrocephalus .

The mortality rate in Germany is 1 percent in the presence of meningitis, with an additional septic course the mortality rate increases to 13 percent, in the case of Waterhouse-Friderichsen syndrome to 33 percent. Whooping cough caused by the pathogen Bordetella pertussis was largely contained through regular vaccinations as early as childhood. However, there is a more cyclical increase in pertussis every four to six years. A reporting requirement was introduced in 2013. 

Infection with the pathogen occurs through the respiratory tract , and multiplication occurs through the mucous membranes. A large number of toxins worsens the defenses of the immune system. The disease is characterized by cough , fever and weakness.

The wheezing characteristic of the disease is due to sudden inspiration from a closed glottis as the attack nears its conclusion. Tuberculosis is an infectious disease that is widespread worldwide. It is caused by mycobacteria and mainly affects the lungs . Spread to other organs and the respiratory tract is possible. 

This disease leads the worldwide mortality statistics. The infection occurs through droplet infection as with common colds. If germs are detected in the sputum , open tuberculosis is present. If external body secretions are carriers of the germs, doctors speak of a potentially open tuberculosis.

Risks, side effects & dangers

The prophylactic use of antivirals and antibiotics is only induced in rare cases to avoid serious infectious diseases. Prophylaxis is primarily used for diseases for which vaccination is not possible and preventive measures make sense, such as malaria.

Chenin, chloroquine, mefloquine, hydroxychloroquine, atoquavone and proguanil are used as drugs. Meningococcal infection is treated with penicillin G. Before being discharged from the hospital, however, the patients receive additional therapy with ciprofloxacin, rifampicin or ceftriaxone, since the antibiotic alone does not kill the pathogens. 

It is still not possible to eradicate whooping cough, as vaccinated people can also become ill. Anti-cellular vaccines, which are combined with antigens, are available for basic immunization. Chemoprophylaxis is based on macrolides. Tuberculosis diseases are treated with drugs specially used for these pathogens, which are therefore called antituberculosis drugs.

It is awarded in the form of primary prophylaxis. Children receive 200 mg/m2 BSA and adults 300 mg/day isoniazid. Taking prophylactic medication can lead to resistance to the medication used, which complicates treatment. So far there is only one government recommendation for treatment with chemoprophylactic drugs: for workers who regularly come into contact with poultry and who are at risk of becoming infected with avian influenza or avian influenza.

Employers are recommended to allow their employees to take chemoprophylaxis with neuraminidase inhibitors. Preventative treatment with oseltamivir phosphate (Tamiflu) to protect against bird flu and influenza is also possible when there is not enough influenza vaccine available.

Website | + posts

Hello! I am Lisa Newlon, and I am a medical writer and researcher with over 10 years of experience in the healthcare industry. I have a Master’s degree in Medicine, and my deep understanding of medical terminology, practices, and procedures has made me a trusted source of information in the medical world.