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Isoniazid / Rifampin Dosage

Applies to the following strengths: 150 mg-300 mg

Usual Adult Dose for:

Usual Geriatric Dose for:

Usual Pediatric Dose for:

Additional dosage information:

Usual Adult Dose for Tuberculosis - Active

2 capsules (300 mg isoniazid and 600 mg rifampin total dose) orally once a day on an empty stomach, either 1 hour before or 2 hours after ingestion of food or antacids.

Duration of Therapy: At least 4 months following the initial treatment phase; continue treatment longer if the patient is still sputum or culture positive, if resistant organisms are present, or if the patient is HIV-positive.

Use: Treatment for pulmonary tuberculosis in which organisms are susceptible, and when the patient has been titrated on the individual components of this combination drug and thus, it has been established that the fixed dosage of this combination drug is therapeutically effective.

Usual Geriatric Dose for Tuberculosis - Active

Use with caution.

Usual Pediatric Dose for Tuberculosis - Active

Younger Than Age 15 Years: The ratio of isoniazid and rifampin in this combination drug may not be appropriate (e.g., pediatric patients usually receive higher mg/kg doses of isoniazid)

Age 15 Years and Older:
2 capsules (300 mg isoniazid and 600 mg rifampin total dose) orally once a day on an empty stomach, either 1 hour before or 2 hours after ingestion of food or antacids, following the initial treatment phase.

Duration of Therapy: At least 4 months following the initial treatment phase; continue treatment longer if the patient is still sputum or culture positive, if resistant organisms are present, or if the patient is HIV-positive.

Use: Treatment for pulmonary tuberculosis in which organisms are susceptible, and when the patient has been titrated on the individual components of this combination drug and thus, it has been established that the fixed dosage of this combination drug is therapeutically effective.

Renal Dose Adjustments

No adjustment recommended; however, carefully monitor use in patients with severe renal dysfunction.

Liver Dose Adjustments


Comments: If this drug is given to patients with impaired liver function, carefully monitor liver function (especially SGPT and SGOT) prior to therapy, then every 2 to 4 weeks during therapy; withdraw treatment if signs of hepatocellular damage occur.

Precautions

US BOXED WARNING:


Safety and efficacy have not been established in patients younger than 15 years.

Consult WARNINGS section for additional precautions.

Dialysis

Data not available.

Other Comments

Administration Advice:


Storage Requirements:

General:

Monitoring:
DERMATOLOGIC: Skin reactions (e.g., signs/symptoms of progressive skin rash often with blisters or mucosal lesions)
GENERAL:
HEPATIC: Baseline measurements of liver function (e.g., hepatic enzymes, bilirubin)
OCULAR: Ophthalmologic exams including ophthalmoscopy (before treatment initiation and periodically thereafter)
OTHER: Collect specimens (bacteriologic smears or cultures) for identification of the infecting organism and to confirm the susceptibility of the organism to rifampin and isoniazid prior to treatment initiation; repeat throughout therapy.

Patient Advice:

Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.