Which class of drugs does isoniazid (INH) belong to?

Isoniazid (INH) is classified as an antitubercular agent, specifically targeting the bacteria that cause tuberculosis. The mechanism of action of isoniazid primarily involves the inhibition of mycolic acid synthesis, which is a critical component of the cell wall of mycobacteria. By disrupting the formation of the cell wall, isoniazid effectively inhibits bacterial growth and leads to the eventual death of the bacteria.

When we examine the other classes mentioned, cell wall synthesis inhibitors directly relate to substances that interfere with the bacterial cell wall formation, which aligns with how isoniazid functions. Protein synthesis inhibitors, on the other hand, target the bacterial ribosomes to prevent protein production, which is not the mechanism of isoniazid. Antiviral agents are specifically designed to combat viral infections, and analgesics are medications that reduce pain. Thus, the classification of isoniazid as a cell wall synthesis inhibitor accurately reflects its role in tuberculosis treatment.