Anti-tuberculosis drugs are medications used to treat tuberculosis (TB), a bacterial infection that primarily affects the lungs but can also affect other parts of the body. The World Health Organization (WHO) has recommended a standard regimen of four drugs for the treatment of TB, which involves an initial phase of two months of intensive therapy followed by a continuation phase of four to six months of therapy with fewer drugs.

The four drugs that make up the standard regimen for TB treatment are:

1. Isoniazid (INH): This is the most important drug used in the treatment of TB. It is a bactericidal drug that works by inhibiting the synthesis of mycolic acids, which are essential components of the bacterial cell wall. INH is usually given orally, once a day.

2. Rifampicin (RIF): This is another important drug used in the treatment of TB. It is a bactericidal drug that works by inhibiting the synthesis of RNA in the bacterial cell. RIF is usually given orally, once a day.

3. Ethambutol (EMB): This drug works by inhibiting the synthesis of cell wall components. It is usually given orally, once a day.

4. Pyrazinamide (PZA): This drug works by lowering the pH inside the bacterial cell, which interferes with the bacterial metabolism. It is usually given orally, once a day.

In addition to these four drugs, other drugs may be used in certain situations, such as when there is drug resistance or when the patient has other medical conditions that require specific drug choices.

The duration of TB treatment depends on the severity of the disease, the patient’s response to therapy, and other factors. It is important to complete the entire course of treatment as prescribed, even if symptoms improve before the treatment is completed.

Like all medications, anti-TB drugs can have side effects. Common side effects include nausea, vomiting, abdominal pain, and skin rashes. Less commonly, more serious side effects may occur, such as liver toxicity or optic neuritis. Patients taking anti-TB drugs should be monitored closely for side effects and any necessary adjustments made to their medication regimen.