Rifampicin is the name given to an antibiotic. It comes from the fungal species Streptomyces mediterranei.
What is rifampicin?
Rifampicin is one of the antibiotics and belongs to the group of rifamycins. It can be used against different types of bacteria. Rifampicin is one of the antibiotics and belongs to the group of rifamycins. It can be used against different types of bacteria. Rifampicin is considered particularly effective in the treatment of tuberculosis, against which it is used together with other drugs. In 1957, the first isolation of the substances from the fungal species Streptomyces mediterranei took place. They have an antibacterial effect. Rifampicin became the most efficient representative of these substances. The antibiotic is produced semi-synthetically from rifamycin B. This substance, in turn, is added to the bacterial genus. This substance is in turn taken from the bacterial genus Amycolatopsis rifamycina. Rifampicin is primarily used to treat infections with mycobacteria. These include not only tuberculosis but also leprosy. In addition, the antibiotic is suitable for treating staphylococci that are resistant to methicillin. Furthermore, it unfolds its effect against Legionella pneumophila and against enterococci.
Pharmacological action
The basis of rifampicin’s mode of action is binding to the bacterial enzyme RNA polymerase. This enzyme is desperately needed by bacteria to make essential proteins. Since they no longer receive this vital protein, the bacteria die as a result. Rifampicin’s action captures bacteria inside the cells as well as germs that are outside. The antibiotic can best exert its effect in an alkaline or neutral environment. This exists primarily outside the cells. In contrast, the positive effect is lower in an acidic environment inside the cells or in cheesy tissue. Rifampicin has the property of killing bacteria. The antibiotic is effective not only against mycobacteria, but also against Gram-positive, Gram-negative and atypical bacteria. These include, for example, Staphylococcus epidermidis, Staphylococcus aureus, Streptococcus viridans, Streptococcus pneumoniae, Haemophilus influenzae, Neisseria meningitidis, and Coxiella burnetii. Rifampicin is administered orally. After ingestion, the antibiotic enters the blood via the intestine. About 80 percent of the antibiotic binds to plasma proteins and is distributed evenly throughout the body. The highest rifampicin concentrations are reached in bile and lungs. Two to five hours after administration, rifampicin passes out of the body again, which happens via bile and stool. If therapy continues for a longer time, this leads to a shortening of the elimination half-life.
Medical use and application
For use, rifampicin is mainly used against tuberculosis. This disease is caused by Mycobacterium tuberculosis. Also among the rifampicin-susceptible mycobacteria are the leprosy pathogens, against which rifampicin is also effective. Furthermore, the drug is suitable for the prevention of meningitis (meningitis), which is caused by meningococci. In this case, it serves to protect the persons in contact with the infected person. With the exception of the treatment of tuberculosis, rifampicin is not a standard antibiotic. It is often used as a reserve antibiotic. This means that it is used when other antibiotics no longer have a positive effect due to resistance. In most cases, rifampicin is administered together with an additional antibiotic. This is usually isoniazid. Rifampicin is usually taken by mouth. If the patient suffers from tuberculosis, the usual daily dose is 10 milligrams of rifampicin per body weight. The drug is usually applied once a day. In the case of other infections, the dosage is 6 to 8 milligrams and is administered twice daily.
Risks and side effects
Adverse side effects are possible in some cases due to the use of rifampicin. For example, mild liver dysfunction often occurs. In the case of a pre-damaged liver, there is a risk of severe side effects. For this reason, the doctor checks the liver functions before the therapy. Checking liver values such as liver enzymes is also considered very important during treatment.In addition, patients taking rifampicin often experience stomach discomfort, loss of appetite, diarrhea, flatulence, nausea, vomiting, weeping skin redness, itching, hives, and fever. Occasionally, changes in the blood count such as a deficiency of white blood cells, platelets or granulocytes are also possible. Anemia, blood clotting disorders, subcutaneous bleeding, menstrual disorders, visual disturbances, asthma-like attacks, and water retention in the tissues or lungs are also possible. If rifampicin is taken irregularly, symptoms similar to influenza sometimes appear. Because rifampicin has an intense reddish-brown coloration of its own, taking the antibiotic can cause body fluids to become discolored. These include sweat, saliva, lacrimal fluid as well as stool and urine. If the patient has hypersensitivity to rifampicin, treatment with the antibiotic must not be performed. The same applies in cases of pronounced liver dysfunction such as jaundice, an inflamed liver or liver cirrhosis, as well as in cases of simultaneous treatment with substances that can have a damaging effect on the liver, such as the anesthetic halothane or the fungal preparation voriconazole. Another contraindication is treatment with HIV-1 protease inhibitors such as indinavir, saquinavir, lopinavir, atazanavir, amprenavir, fosamprenavir, tipranavir, nelfinavir or darunavir. During pregnancy, treatment of acute tuberculosis with rifampicin is generally possible. However, other diseases should be treated with more suitable antibiotics. For example, there is a risk that prolonged use of the drug may lead to the inhibition of coagulation factors that are dependent on vitamin K. Treatment during breastfeeding, on the other hand, is not considered risky for the infant.
