Starting multi-drug therapy for TB is primarily to prevent what?

Starting multi-drug therapy for TB is primarily to prevent what?

• A. To prevent resistance
• B. To reduce cost
• C. To shorten treatment
• D. To avoid liver toxicity

Answer: (A)

Using several anti-TB drugs together is chosen primarily to prevent the emergence of drug-resistant TB. Mycobacteria can acquire mutations that confer resistance to a particular drug; with a single agent, those resistant bacteria survive and multiply, leading to resistant TB. By applying multiple drugs with different targets, a bacterium would need to develop several independent resistance mutations at once to survive the regimen, which is highly unlikely. This dramatically lowers the chance that resistance will arise during treatment and helps ensure the cure for the individual and the safety of the community by limiting the spread of resistant strains. While considerations like cost or potential toxicity exist, they are not the main reason for starting multi-drug therapy; the priority is keeping TB treatment effective by preventing drug resistance.

Using several anti-TB drugs together is chosen primarily to prevent the emergence of drug-resistant TB. Mycobacteria can acquire mutations that confer resistance to a particular drug; with a single agent, those resistant bacteria survive and multiply, leading to resistant TB. By applying multiple drugs with different targets, a bacterium would need to develop several independent resistance mutations at once to survive the regimen, which is highly unlikely. This dramatically lowers the chance that resistance will arise during treatment and helps ensure the cure for the individual and the safety of the community by limiting the spread of resistant strains. While considerations like cost or potential toxicity exist, they are not the main reason for starting multi-drug therapy; the priority is keeping TB treatment effective by preventing drug resistance.