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Nydrazid Side Effects

Generic name: isoniazid

Medically reviewed by Drugs.com. Last updated on Jan 28, 2024.

Note: This document provides detailed information about Nydrazid Side Effects associated with isoniazid. Some dosage forms listed on this page may not apply specifically to the brand name Nydrazid.

Applies to isoniazid: solution, tablet.

Important warnings This medicine can cause some serious health issues

Intramuscular route (solution)

Severe and sometimes fatal hepatitis has been reported with isoniazid therapy and may occur even after many months of treatment.

The risk for hepatitis increases with advancing age, concomitant alcohol use, chronic liver disease, and injection drug use.

Patients given isoniazid should be carefully monitored and interviewed at monthly intervals.

For persons 35 and older, in addition to monthly symptom reviews, hepatic enzymes (specifically, AST and ALT (formerly SGOT and SGPT, respectively) should be measured prior to starting isoniazid therapy and periodically throughout treatment.

An increased risk of fatal hepatitis associated with isoniazid has been reported in women, particularly black and Hispanic women.

The risk may also be increased during the post partum period.

More careful monitoring should be considered in these groups, possibly including more frequent laboratory monitoring.

Oral route (tablet; syrup)

Severe and sometimes fatal hepatitis has been reported with isoniazid therapy and may occur even after many months of treatment.

The risk for hepatitis increases with advancing age, concomitant alcohol use, chronic liver disease, and injection drug use.

Patients given isoniazid should be carefully monitored and interviewed at monthly intervals.

For persons 35 and older, in addition to monthly symptom reviews, hepatic enzymes (specifically, AST and ALT (formerly SGOT and SGPT, respectively) should be measured prior to starting isoniazid therapy and periodically throughout treatment.

An increased risk of fatal hepatitis associated with isoniazid has been reported in women, particularly black and Hispanic women.

The risk may also be increased during the post partum period.

More careful monitoring should be considered in these groups, possibly including more frequent laboratory monitoring.

Serious side effects of Nydrazid

Along with its needed effects, isoniazid (the active ingredient contained in Nydrazid) may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.

Check with your doctor immediately if any of the following side effects occur while taking isoniazid:

More common

  • clumsiness or unsteadiness
  • dark urine
  • loss of appetite
  • nausea or vomiting
  • numbness, tingling, burning, or pain in hands and feet
  • unusual tiredness or weakness
  • yellow eyes or skin

Rare

  • blurred vision or loss of vision, with or without eye pain
  • convulsions (seizures)
  • fever and sore throat
  • joint pain
  • mental depression
  • mood or other mental changes
  • skin rash
  • unusual bleeding or bruising

Other side effects of Nydrazid

Some side effects of isoniazid may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. Also, your health care professional may be able to tell you about ways to prevent or reduce some of these side effects.

Check with your health care professional if any of the following side effects continue or are bothersome or if you have any questions about them:

More common

  • diarrhea
  • stomach pain

For injection form

Dark urine and yellowing of the eyes or skin (signs of liver problems) are more likely to occur in patients over 50 years of age.

For healthcare professionals

Applies to isoniazid: intramuscular solution, oral syrup, oral tablet.

General

The most commonly reported side effects included mild and transient elevation of serum transaminase levels, peripheral neuropathy, and hepatitis.[Ref]

Hepatic

Nervous system

Hepatic

Mild and transient elevation in serum transaminases usually occurred in the first 1 to 6 months of treatment, but could occur at any time during treatment. Transaminase levels returned to normal with continued treatment in most cases.[Ref]

Nervous system

Peripheral neuropathy usually occurred with doses over 5 mg/kg.[Ref]

Dermatologic

Hematologic

Metabolic

Gastrointestinal

Other

Psychiatric

Musculoskeletal

Ocular

Genitourinary

Cardiovascular

Endocrine

Immunologic

Local

References

1. "Product Information. INH (isoniazid)." Ciba Pharmaceuticals, Summit, NJ.

2. (2001) "Product Information. Nydrazid (isoniazid)." Apothecon Inc

3. Cerner Multum, Inc. "UK Summary of Product Characteristics."

4. (2006) "Product Information. Isoniazid (isoniazid)." Barr Laboratories Inc

5. Cerner Multum, Inc. "Australian Product Information."

Further information

Nydrazid side effects can vary depending on the individual. Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.

Some side effects may not be reported. You may report them to the FDA.