Isoniazid is an oral antibiotic. Depending on the condition for which it is being used, patients may need to take isoniazid for months. During treatment, monthly liver function tests are needed. In addition, patients may need to take vitamin B6 supplements. Patients should take the entire course their doctor has prescribed to prevent antibiotic resistance.
This antibiotic is a common bacterial infection treatment. Of course, it is most often prescribed as a tuberculosis treatment. It can be prescribed alongside other oral antibiotics for some cases. It does not come as an antibiotic cream or ointment. Finally, patients must understand how it works before taking it.
How It Works
As an antibiotic, isoniazid fights bacteria. Specifically, it stops the mycobacterial cell wall from forming. This prodrug is activated by a bacterial enzyme called KatG, and it kills rapidly dividing mycobacteria. This antibiotic is bacteriostatic for bacteria that are slow to grow. It blocks the cytochrome P450 system and functions as a source of free radicals.
Individuals should note that this drug is also a mild monoamine oxidase inhibitor (MAOI). The liver is responsible for metabolizing this medication. It is vital to note that some patients metabolize it significantly faster. Thus, research is being done to determine the reason for this difference.