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Isoniazid Oral Tablet (ISONIAZID - ORAL)

This medicine is used for the following purposes:

  • infections caused by bacteria
  • tuberculosis

Generic Name: Isoniazid

Instructions

You may break or cut the pill if necessary.

Take the medicine on an empty stomach.

Take on empty stomach - 1 hour before or 2 hours after eating.

This medicine will work best if you take it at about the same time every day.

Store at room temperature away from heat, light, and moisture. Do not keep in the bathroom.

Do not take any antacids or vitamins with aluminum for 1 hour before or 1 hour after taking this medicine.

It is very important to avoid some foods while on this medicine. Please ask your doctor or nurse to provide you with a list of foods you should avoid.

If you forget to take a dose on time, take it as soon as you remember. If it is almost time for the next dose, do not take the missed dose. Return to your normal schedule. Do not take 2 doses at one time.

Drug interactions can change how medicines work or increase risk for side effects. Tell your health care providers about all medicines taken. Include prescription and over-the-counter medicines, vitamins, and herbal medicines. Speak with your doctor or pharmacist before starting or stopping any medicine.

The foods you eat can change how well this medicine works. Tell your doctor about the types of food you normally eat. Ask your doctor for a list of foods that can affect this medicine. Do not significantly change the foods you normally eat while on this medicine.

Keep using this medicine for the full number of days that it is prescribed. Do not stop the medicine even if you start to feel better.

Keep all appointments for medical exams and tests while on this medicine.

Cautions

Tell your doctor and pharmacist if you ever had an allergic reaction to a medicine.

This medicine is associated with a rare but very serious medical condition. Please speak with your doctor about symptoms you should look out for while on this medicine. Notify your doctor immediately if you develop those symptoms.

Some patients taking this medicine have experienced serious side effects. Please speak with your doctor to understand the risks and benefits associated with this medicine.

Do not use the medication any more than instructed.

Please check with your doctor before drinking alcohol while on this medicine.

Speak with your health care provider before receiving any vaccinations.

Tell the doctor or pharmacist if you are pregnant, planning to be pregnant, or breastfeeding.

Do not share this medicine with anyone who has not been prescribed this medicine.

Always refill this medicine before it runs out.

Side Effects

The following is a list of some common side effects from this medicine. Please speak with your doctor about what you should do if you experience these or other side effects.

  • nausea and vomiting
  • stomach upset or abdominal pain

If you have any of the following side effects, you may be getting too much medicine. Please contact your doctor to let them know about these side effects.

  • shallow, irregular breathing

Call your doctor or get medical help right away if you notice any of these more serious side effects:

  • bleeding or bruising
  • blurry vision
  • confusion
  • fever
  • swelling in the neck or throat
  • numbness or tingling in hands and feet
  • hallucinations (unusual thoughts, seeing or hearing things that are not real)
  • pain in the joints
  • signs of liver damage (such as yellowing of eye or skin, dark urine, or unusual tiredness)
  • seizures
  • light colored stool
  • persistent or unusual thirst
  • increased urinary frequency
  • blurring or changes of vision

A few people may have an allergic reaction to this medicine. Symptoms can include difficulty breathing, skin rash, itching, swelling, or severe dizziness. If you notice any of these symptoms, seek medical help quickly.

Please speak with your doctor, nurse, or pharmacist if you have any questions about this medicine.