isoniazid - oral (cont.)
SIDE EFFECTS: See also Warning section.Nausea/vomiting or stomach upset may occur. If any of these effects persist or worsen, tell your doctor or pharmacist promptly.Remember that your doctor has prescribed this medication because he or she has judged that the benefit to you is greater than the risk of side effects. Many people using this medication do not have serious side effects.Tell your doctor immediately if any of these unlikely but serious side effects occur: numbness/tingling of arms/legs, painful/swollen joints.Tell your doctor immediately if any of these rare but serious side effects occur: change in the amount of urine, increased thirst/urination, vision changes, easy bruising/bleeding, signs of a new infection (such as fever, persistent sore throat), mental/mood changes (such as confusion, psychosis), seizures.A very serious allergic reaction to this drug is rare. However, seek immediate medical attention if you notice any symptoms of a serious allergic reaction, including: rash, itching/swelling (especially of the face/tongue/throat), severe dizziness, trouble breathing.This is not a complete list of possible side effects. If you notice other effects not listed above, contact your doctor or pharmacist.In the US -Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.In Canada - Call your doctor for medical advice about side effects. You may report side effects to Health Canada at 1-866-234-2345.
PRECAUTIONS: See also Warning section.Before taking isoniazid, tell your doctor or pharmacist if you are allergic to it; or if you have any other allergies. This product may contain inactive ingredients, which can cause allergic reactions or other problems. Talk to your pharmacist for more details.Before using this medication, tell your doctor or pharmacist your medical history, especially of: previous severe reaction from isoniazid (such as liver disease), liver disease, alcohol use, HIV infection, kidney disease, diabetes, numbness/tingling of arms/legs (peripheral neuropathy), recent childbirth.Before having surgery, tell your doctor or dentist about all the products you use (including prescription drugs, nonprescription drugs, and herbal products).Alcohol may increase the risk of liver disease. Avoid alcoholic beverages while using this medication.This product may cause live bacterial vaccines (such as BCG vaccine) not to work as well. Therefore, do not have any immunizations/vaccinations while using this medication without the consent of your doctor.Liquid forms of this medication may contain sugar. Caution is advised if you have diabetes or any other condition that requires you to limit/avoid sugar. Ask your doctor or pharmacist about using this product safely.During pregnancy, this medication should be used only when clearly needed. Discuss the risks and benefits with your doctor.This product passes into breast milk but is unlikely to harm a nursing infant. Consult your doctor before breast-feeding.
Medically Reviewed by a Doctor on 4/16/2014
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You are encouraged to report negative side effects of prescription drugs to the FDA. Visit the FDA MedWatch website or call 1-800-FDA-1088.
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