Drug Status in USA : Approved Drug Status in Canada : Approved
pronunciation
pronounced as (eye soe nye' a zid)
Why is this medication prescribed?
Isoniazid is used alone or with other drugs to treat tuberculosis (TB) and to prevent it in people who have had contact with tuberculosis bacteria. It eliminates only active (growing) bacteria. Since the bacteria may exist in a resting (nongrowing) state for long periods, therapy with isoniazid (and other antituberculosis drugs) must be continued for a long time (usually 6 to 12 months).
This medication is sometimes prescribed for other uses; ask your doctor or pharmacist for more information.
How should this medicine be used?
Isoniazid comes as a tablet, capsule, and a syrup to take by mouth. It is also available as an extended release tablet. It usually is taken once a day, on an empty stomach, 1 hour before or 2 hours after meals. However, if isoniazid causes an upset stomach, it may be taken with food. Follow the directions on your prescription label carefully, and ask your doctor or pharmacist to explain any part you do not understand. Take isoniazid exactly as directed. Do not take more or less of it or take it more often than prescribed by your doctor.
What are the precautions to be followed?
Before taking isoniazid,
tell your doctor and pharmacist if you are allergic to isoniazid or any other drugs.
tell your doctor and pharmacist what prescription and nonprescription medications you are taking, especially acetaminophen (Tylenol), antacids, carbamazepine (Tegretol), disulfiram (Antabuse), ketoconazole (Nizoral), phenytoin (Dilantin), theophylline (Theobid, Theo-Dur), valproic acid (Depakene, Depakote), and vitamins.
in addition to the conditions listed in the IMPORTANT WARNING section, tell your doctor if you have or have ever had kidney disease; diabetes; tingling, burning, and pain in the fingers or toes (peripheral neuropathy); or human immunodeficiency virus (HIV).
tell your doctor if you are pregnant or plan to become pregnant. If you become pregnant while taking isoniazid, call your doctor.
be aware that you should not drink alcoholic beverages while taking this drug.
What are possible side effects of this medication ?
Isoniazid may cause side effects. Tell your doctor if any of these symptoms are severe or do not go away:
diarrhea
vision problems
If you experience any of the following symptoms or those listed in the IMPORTANT WARNING section, call your doctor immediately:
eye pain
numbness or tingling in the hands and feet
skin rash
fever
swollen glands
sore throat
unusual bleeding or bruising
stomach pains or tenderness
How to store the medication and dispose it of after its use later?
Keep this medication in the container it came in, tightly closed, and out of reach of children. Store it at room temperature and away from excess heat and moisture (not in the bathroom). Throw away any medication that is outdated or no longer needed. Talk to your pharmacist about the proper disposal of your medication.
Drug Category/Class
Hydrazides
Cytochrome P-450 CYP1A2 Inhibitors
Cytochrome P-450 CYP1A2 Inducers
CYP2A6 Inhibitors
CYP2A6 Inhibitors (strong)
CYP2A6 Inhibitors (moderate)
CYP2A6 Inducers
CYP2A6 Inducers (strong)
CYP2E1 Inhibitors
CYP2E1 Inducers
CYP2E1 Inducers (strong)
Cytochrome P-450 CYP2C9 Inhibitors
Cytochrome P-450 CYP2C9 Inducers
Cytochrome P-450 CYP2C19 Inducers
Cytochrome P-450
Prescribed
For the treatment of all forms of tuberculosis in which organisms are susceptible.