isoniazid - oral (cont.)
USES: Isoniazid is used with other medications to treat active tuberculosis (TB) infections. It is also used alone to prevent active TB infections in people who may be infected with the bacteria (people with positive TB skin test). Isoniazid is an antibiotic and works by stopping the growth of bacteria.This antibiotic treats only bacterial infections. It will not work for viral infections (such as common cold, flu). Unnecessary use or misuse of any antibiotic can lead to its decreased effectiveness.
HOW TO USE: Take this medication by mouth on an empty stomach (1 hour before or 2 hours after meals) as directed by your doctor. If you are using the liquid form of this medication, carefully measure the dose using a special measuring device/spoon. Do not use a household spoon because you may not get the correct dose.If you also take antacids that contain aluminum, take this medication at least 1 hour before the antacid.Dosage is based on your age, weight, medical condition, and response to treatment.Antibiotics work best when the amount of medicine in your body is kept at a constant level. Therefore, take this drug at evenly spaced intervals. If you are taking this medication daily, take it at the same time each day. If you are taking this medication on a weekly schedule, take it on the same day(s) of the week and at the same time each day. Mark the days on the calendar when you need to take the medication.Continue to take this medication (and other TB medications) until the full prescribed amount is finished, even if symptoms disappear. Stopping the medication too early or skipping doses may allow the bacteria to continue to grow, which may result in a return of the infection and cause the infection to be more difficult to treat (resistant).Your doctor may also direct you to take vitamin B6 (pyridoxine) to help prevent certain side effects (such as nerve problems) from isoniazid. Follow your doctor's instructions carefully.Isoniazid may interact with foods containing tyramine/histamine (such as cheese, red wine, certain types of fish). This interaction may cause increased blood pressure, flushing of the skin, headache, dizziness, or fast/pounding heartbeat. Tell your doctor immediately if any of these symptoms occur. Your doctor may recommend that you follow a special diet while taking this medication. Consult your doctor for more details.Tell your doctor if your condition persists or worsens.
Medically Reviewed by a Doctor on 4/16/2014
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