isoniazid + rifampin + ethambutol + pyrazinamide

The 2HERZ + 4HRE regimen is the standard six-month antibiotic course for treating drug-susceptible pulmonary tuberculosis (TB). It consists of an intensive phase lasting two months, during which patients receive a four-drug combination of isoniazid (H), rifampin (R), ethambutol (E), and pyrazinamide (Z). This is followed by a four-month continuation phase using isoniazid, rifampin, and ethambutol (HRE). The regimen is designed to rapidly reduce the bacterial load and eliminate persistent Mycobacterium tuberculosis bacilli to prevent relapse and the development of drug resistance. Kaohsiung Veterans General Hospital has been involved in clinical trials (such as NCT05434390) evaluating the safety and efficacy of this standard regimen compared to shorter four-month courses in low-risk active TB patients. The individual components work through distinct mechanisms: isoniazid inhibits mycolic acid synthesis, rifampin inhibits bacterial RNA polymerase, ethambutol interferes with cell wall biosynthesis, and pyrazinamide disrupts bacterial membrane energetics.

Brand names

RifafourVoractivAkuriT-4AkuriT4AkuriT 4Forecox

Other names

Standard 6-month tuberculosis regimenStandard6-month tuberculosis regimenStandard-6-month tuberculosis regimenWHO standard TB regimen2HERZ + 4HRE