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Important Note

The following information is intended to supplement, not substitute for, the expertise and judgment of your physician, pharmacist or other healthcare professional. It should not be construed to indicate that use of the drug is safe, appropriate, or effective for you. Consult your healthcare professional before using this drug.





This is used with other medication in the treatment of tuberculosis infections. It is also used to treat certain types of urinary tract infections.

How To Use

Take this by mouth as directed usually every 12 hours for the first two weeks. This medication works best when the amount of medicine in your body is kept at a constant level. Do this by taking the medication at evenly spaced intervals throughout the day and night. Continue using this for the full time prescribed. It may be necessary to continue therapy for tuberculosis for several months to one year or more. Stopping the medication too early may result in ineffective treatment.

Side Effects

Drowsiness may occur. If it continues or becomes severe, inform your doctor. Notify your doctor if you experience: dizziness, headache, tremor, slurred speech, tingling of the hands or feet, mental confusion, irritability, anxiety, skin rash. If you notice other effects not listed above, contact your doctor or pharmacist.


Tell your doctor your medical history, especially of: kidney disease, epilepsy, depression, anxiety, mental illness, any allergies. Use caution driving or performing tasks requiring alertness since this may cause drowsiness. Use of alcohol increases the risk and severity of these side effects. It is recommended to limit intake of alcoholic beverages while taking this medication. This medication should be used only if clearly needed during pregnancy. This drug is excreted into breast milk and is not recommended for use while breast-feeding. Consult your doctor before breast-feeding.

Drug Interactions

Tell your doctor of any nonprescription or prescription medication you may take particularly: other anti-tuberculosis medication (e.g., isoniazid, ethionamide, pyridoxine). Do not start or stop any medicine without doctor or pharmacist approval.


If overdose is suspected, contact your local poison control center or emergency room immediately. Symptoms of overdose may include dizziness, confusion, drowsiness, headache, seizures, and loss of consciousness.


Laboratory tests will be done frequently while taking this to monitor its effects and prevent side effects.

Missed Dose

It is important to receive each dose as scheduled. If you miss a dose, use it as soon as you remember. If it is near the time of the next dose, skip the missed dose and resume your usual dosing schedule. Do not "double-up" the dose to catch up.


Store at room temperature between 59 and 86 degrees F (15 to 30 degrees C) away from moisture and light as directed. Do not store in the bathroom. Keep out of the reach of children.