Antitubercular therapy refers to the treatment regimen used to combat tuberculosis, primarily involving a combination of antibiotics to ensure the complete eradication of Mycobacterium tuberculosis and prevent drug resistance. The standard therapy often includes the use of isoniazid, rifampicin, ethambutol, and pyrazinamide over a period of six months or more, depending on the patient's response and the presence of drug-resistant strains.