Izoniaside: What is it? Presentations, Uses, Dosage, Adverse Effects and Warnings

It is an active antituberculous drug against Mycobacterium tuberculosis.

Presentations of Izoniasida


  • 50 mg.
  • 100 mg.
  • 300 mg.

Oral syrup:

  • 50 mg / 5 ml.

Injectable solution:

  • 100 mg / ml.

Uses and dosage

Latent Tuberculosis (TB) infection

The treatment of latent TB infection dramatically reduces the risk of TB infection progressing and improving the disease.

  • 30 kg: 300 mg PO qDía x 9 meses.

3-month regimen

It is recommended for patients 12 years of age or older at high risk of developing TB disease, including anyone who has recently had exposure to contagious TB, conversion from negative to positive into a TB infection test or a chest x-ray that indicates previous disease TB.

People with HIV who do not take antiretrovirals can also use this regimen:


  • 900 mg PO once a week x 3 months (administer with 900 mg rifapentine once a week).

Administered as DOT

It is not recommended for children under two years of age, pregnant women, or women who plan to become pregnant.

In the case of people infected with HIV who take antiretrovirals and patients whose tuberculosis infection is presumed to result from exposure to a person with TB disease that is resistant to 1 of the two drugs.

Active tuberculosis disease

  • 5 mg / kg PO / IM qDia, sin exceder 300 mg qDia.
  • 15 mg / kg PO / IM above; it should not exceed 900 mg 1-3 times / week.

They are used in a multidrug regimen containing rifampin (or rifabutin or rifapentine), pyrazinamide, and ethambutol.

Duration of treatment is dependent on the regimen consisting of an initial phase of treatment and a continuation phase of treatment:


  • With rifampin (Rifamate)
  • With rifampin and pyrizinamide (Rifater)

Other indications and uses

Newly infected patients:

At this point, family members and people close to people recently diagnosed with tuberculosis can be analyzed to discard possible infections:

  • Cutaneous test + ve of tuberculosis with + ve non-progressive chest x-ray.
  • + tuberculosis skin test with underlying disease or immunosuppression.
  • + skin test with TB, <35 years of age; > 35 years weigh the use against the risk of hepatitis.

Medical opinions

The medical community remains skeptical about the efficiency of methods and healing practices to counteract, prevent and eradicate influenza. Well, experts warn about the severe flu and the low efficacy of the vaccine.

They also say that influenza activity is as widespread as the 2009 pandemic. However, studies continue to look for medical solutions.

Adverse effects of Izoniaside

Among the side effects caused by Izoniaside can be listed:

  • Peripheral neuropathy (incidence related to the dose, 10-20% with 10 mg/kg / day).
  • Loss of appetite
  • Nausea.
  • He retched.
  • Stomach ache.
  • Weakness 1-10%.
  • Dizziness.
  • Lethargy.
  • Progressive liver damage (increases with age, 2.3% in pts> 50 yo).
  • Hyperreflexia.
  • Agranulocytosis.
  • Anemia.
  • Megaloblastic anemia.
  • Thrombocytopenia .
  • Systemic lupus erythematosus.

Other adverse reactions reportedpancreatitis, toxic epidermal necrolysis, and drug reaction with eosinophilia syndrome (DRESS)


In the first three months of treatment and many months after treatment, severe and sometimes fatal hepatitis can occur. The risk is related to age and increases with daily consumption of alcohol.

Patients should be instructed on the signs and symptoms of hepatitis.

Contraindications of Izoniaside

Injury or previous hepatic reaction INH, acute liver, pancreatitis.


Isoniazid is contraindicated in patients who develop severe hypersensitivity reactions, including drug-induced hepatitis, liver injury associated with previous isoniazid, severe adverse reactions to isoniazid, such as drug fever, chills, arthritis, and acute liver disease of any etiology.


  • Avoid the consumption of alcohol or illicit injectable drugs.
  • Have a predisposition to neuropathy.
  • Malnutrition
  • Severe renal failure.
  • Chronic liver DZ.

Other antituberculous agents

Administer pyridoxine (B6) at the same time for pregnant women, malnourished patients, or those with neuropathic diathesis.

Keep in mind that alcohol consumption and kidney or liver dysfunction will affect serum levels.

Breastfeeding and pregnancy

Pregnancy category: C.

Lactation: Transfer to milk but safe for infants.

Understanding pregnancy categories:

  • A: Generally acceptable, controlled studies in pregnant women show no evidence of fetal risk.
  • B:  maybe acceptable, or animal studies show no risk, but studies in humans are not available, or studies in animals showed minor risks, and studies were conducted in humans and showed no risk.
  • C: use with caution if the benefits outweigh the risks. Studies in animals show risk studies and humans are not available, or studies were not conducted in animals or humans.
  • D: use it in life-threatening emergencies when no safer medication is available. Positive evidence of human fetal risk.
  • X: not used in pregnancy. The risks involved outweigh the potential benefits. There are safer alternatives.