Rifampicin Mechanism of Action | Detailed Explanation

Rifampicin is an artificial semi-synthetic of rifamycin SV, an orange-red crystalline powder. Rifampicin is also a topical antifungal drug, mainly used for the treatment of various types of tuberculosis and tuberculous meningitis. So what’s the rifampicin mechanism of action, let’s move on to learn more about it.

Rifampicin Mechanism of Action

Rifampicin specifically binds to the beta subunit of bacterial DNA-dependent RNA polymerase, thereby impeding mRNA synthesis.

Rifampicin has a broad and potent antibacterial spectrum, acting against both resting and multiplying bacteria and increasing the antibacterial activity of streptomycin and isoniazid. Rifampicin not only acts against Mycobacterium tuberculosis but also kills many G+ and G-. The antibacterial strength of rifampicin is related to its concentration, low concentration inhibits bacteria, high concentration kills bacteria, and its efficacy is comparable to isoniazid.

The antimicrobial mechanism is specific binding to bacterial-dependent DNA and RNA polymerase subunit units, hindering RNA synthesis, and has no effect on RNA polymerase in human and animal cells. Rifampicin is highly penetrating and widely distributed in vivo, including cerebrospinal fluid, pleural and abdominal fluid, tuberculosis cavities, sputum, and placenta. After absorption from the gastrointestinal tract, rifampicin is excreted mainly in bile for enterohepatic circulation.

Clinical Applications of Rifampicin

Understanding the rifampicin mechanism of action, next, we will learn about the main clinical uses of rifampicin.

Rifampicin has four main clinical applications.

First, rifampicin is used in combination with other anti-tuberculosis drugs for the primary and secondary treatment of various types of tuberculosis (including tuberculous meningitis). Second, rifampicin can be used in combination with other drugs for the treatment of leprosy and non-tuberculous mycobacterial infections. In addition, rifampicin can be used with vancomycin (intravenously) to treat serious infections caused by methicillin-resistant staphylococci. Finally, in asymptomatic carriers of Neisseria meningitidis, rifampicin clears Neisseria meningitidis from the nasopharynx (but is not indicated for Neisseria meningitidis infections).

Adverse effects of taking rifampicin

First, after taking rifampicin, digestive reactions are common, manifested as anorexia, nausea, vomiting, epigastric discomfort, diarrhea, etc.; second, high-dose intermittent therapy can appear as "flu syndrome", manifested as chills, chills, fever, muscle pain and other symptoms similar to the common cold; lastly, the most common adverse reaction to rifampicin is hepatotoxicity. Jaundice, hepatomegaly, hepatic dysfunction, and other symptoms can occur with long-term large amounts of rifampicin, and severe cases can be fatal. In addition, after patients take this product, urine and feces, saliva, tears, etc. can be orange-red.

How to take rifampicin

Why should rifampicin be taken on an empty stomach with warm boiled water? First of all, Rifampicin is one of the commonly used antimicrobials for anti-tuberculosis treatment. Taking Rifampicin on an empty stomach ensures the effectiveness of Rifampicin. If Rifampicin is taken after eating, the absorption of the drug will be reduced by 30%, which will greatly affect the therapeutic effect of Rifampicin.

Secondly, take Rifampicin orally with warm boiled water so that the body's blood concentration can reach its peak after 1.5 hours to 4 hours. It is important to note that the tablets should not be taken with milk, soymilk, fruit juices, or tea when taking rifampicin. It is best to eat two hours after taking rifampicin, i.e. eating can affect the effectiveness of the treatment.

Thirdly, during the period of taking Rifampicin, sweat, urine, tears, etc. will turn dark red, this is a normal phenomenon, so do not need to be too nervous.

In addition, there are the following precautions for taking rifampicin:

First, pregnant women within 3 months are prohibited. Second, avoid drinking alcohol during the medication. Third, the use of rifampicin alone in the treatment of tuberculosis can rapidly develop drug resistance, so this product must be used in combination with other drugs. Fourthly, rifampicin should be taken orally on an empty stomach early in the morning because eating affects the absorption of rifampicin.

Conclusion

Tuberculosis is a chronic infectious disease caused by Mycobacterium tuberculosis, which can affect many organs of the body, and is more common in the lungs. Reasonable chemotherapy for tuberculosis is the key to controlling disease progression, and recurrence and inhibiting the development of drug resistance in Mycobacterium tuberculosis.

There are many types of anti-tuberculosis drugs currently used in the clinic, and usually those with high efficacy, fewer adverse effects and more easily tolerated by patients become the first-line anti-tuberculosis drugs, and rifampicin is one of these drugs. Understanding the rifampicin mechanism of action, its clinical application, and how to take it will also help our health in many ways.