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If I have TB Infection, How Can I Keep from Developing TB Disease?

Many people who have TB infection never develop TB disease.  But some people who have TB infection are more likely to develop TB disease than others.   These people are at high risk for TB disease.  They include.

• People with HIV infection

• people in close contact with a person who has infectious TB

• people who became infected with TB bacteria in the last 2 years

• babies and young children

• people who inject drugs

• people who are sick with other diseases that weaken the immune system

• elderly people

If you have TB infection (a positive skin test reaction) and you are in one of these high-risk groups, you need to take medicine to keep from developing TB disease.  This kind of treatment is called preventive therapy.  Also, if you are younger than 35 and you have TB infection, you may benefit from preventive therapy even if you are not in a high-risk group.

People who have TB infection but do not receive preventive therapy need to know the symptoms of TB.  If they develop symptoms of TB disease later on, they should see a doctor right away.

The medicine usually used for preventive therapy is a drug called isoniazid or INH.  INH kills the TB bacteria that are inactive in the body.  If you take your medicine as prescribed, preventive therapy will keep you from ever developing TB disease.

Most people must take INH for at least 6 months.  Children and people with HIV infection need to take INH for a longer time.

Sometimes people are given preventive therapy even if their skin test reaction is not positive.  This is often done with infants, children, and HIV-infected people who have recently spent time with someone with infectious TB disease.   This is because they are at very high risk of developing serious TB disease soon after they become infected with TB bacteria.

It is important that you take all the pills prescribed for you so that your preventive therapy is effective.  If you start taking INH, you will need to see your doctor or nurse on a regular schedule.  He or she will check on how you are doing.  Very few people have serious side effects in INH.  However, if you have any of the following side effects, call your doctor or nurse right away:

• no appetite

• nausea

• vomiting

• yellowish skin or eyes

• fever for 3 or more days

• abdominal pain

• tingling in the fingers and toes

• Warning: Drinking alcoholic beverages (wine, beer, and liquor) while taking INH can be dangerous.  Check with your doctor or nurse for more information.

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