How Effective Is Isoniazid for Tuberculosis?

Isoniazid for tuberculosis can be highly effective if patients take it as directed and their medical providers monitor them through therapy. This drug can be used in the treatment of both active and latent infections with the bacteria that cause this disease to kill them off and limit damage to the patient’s lungs. It comes with some potentially serious side effects including liver damage and acute toxicity; this makes it important to undergo screening before starting therapy and regularly attend follow-up appointments.

This drug was developed in the early 20th century and introduced for tuberculosis treatment in the 1960s. On its own, isoniazid for tuberculosis is not usually very effective because the bacteria can rapidly develop resistance. In combination therapy with other medications, it can help comprehensively address an infection. The medication needs to be taken for an extended period of time, up to nine months in some cases, which can become a problem if the patient has trouble adhering to the treatment regimen.

With cases of latent tuberculosis, where the patient has positive signs of exposure but a clear lung x-ray, isoniazid for tuberculosis can be used in aggressive combination therapy for an initial short course to kill as many bacteria as possible. Follow-up treatment eradicates the remainders. Over the course of this treatment, the patient needs regular checkups to monitor liver function, check for signs that active tuberculosis is developing, and evaluate for other side effects.

Patients with active tuberculosis can also use isoniazid as part of their combination drug therapy. In their case, the medication kills bacteria to suppress the infection and can help control the spread of disease. People using isoniazid for tuberculosis in these circumstances also need to be monitored to make sure the medication is working safely. If they develop side effects, other drugs can be swapped into the combination therapy to attack the tuberculosis bacteria from a new angle.

It is important to take this medication as directed so it can be most effective. It should be taken at least half an hour before a meal or two hours after so the body has time to fully absorb it. Isoniazid for tuberculosis shouldn’t be taken at the same time as medications to cut down on stomach acid and irritation, as these can also interfere with absorption and make it less effective. Patients may not be able to take the drug if they have severe liver dysfunction, and shouldn’t drink while using it because this may compromise the liver.