Dosing and uses of Trecator SC (ethionamide)
Adult dosage forms and strengths
tablet
- 250mg
Tuberculosis, Active
15-20 mg/kg/day PO
Initiate dose at 250 mg/day for 1-2 days; THEN increase to 250 mg twice daily for 1-2 days with gradual increases to highest tolerated dose; 750 mg/day average dose
Not to exceed 1000 mg/day in 3-4 divided doses
Renal Impairment
End-stage renal disease on hemodialysis: 250-500 mg/day
CrCl <30 mL/min: 250-500 mg/day
CrCl ≥ 30 mL/min: No dose adjustment necessary
Administration
Part of multi-drug regimen; not first-line treatment
Take with food
Dosing Considerations
If susceptibility tests indicate that the patient's organism is resistant to one of first-line antituberculosis drugs (i.e., isoniazid or rifampin) yet susceptible to ethionamide, ethionamide should be accompanied by at least one drug to which M. tuberculosis isolate is known to be susceptible;3 if tuberculosis is resistant to both isoniazid and rifampin, yet susceptible to ethionamide, ethionamide should be accompanied by at least two other drugs to which the M. tuberculosis isolate is known to be susceptible
Directly observed therapy is recommended for all patients receiving treatment for tuberculosis
Monitor: baseline & periodic LFTs, TFTs, glucose
Pediatric dosage forms and strengths
tablet
- 250mg
Tuberculosis, Active
M. tuberculosis resistant to isoniazid or rifampin, or patient intolerant to drugs
10-20 mg/kg/day divided BID/TID PO Or
15 mg/kg PO qDay
No more than 1000 mg/day in 3-4 divided doses
Administration
Part of multi-drug regimen; not first-line treatment
Take after meals
Dosing Considerations
If susceptibility tests indicate that the patient's organism is resistant to one of first-line antituberculosis drugs (i.e., isoniazid or rifampin) yet susceptible to ethionamide, ethionamide should be accompanied by at least one drug to which M. tuberculosis isolate is known to be susceptible; if tuberculosis is resistant to both isoniazid and rifampin, yet susceptible to ethionamide, ethionamide should be accompanied by at least two other drugs to which the M. tuberculosis isolate is known to be susceptible
Directly observed therapy is recommended for all patients receiving treatment for tuberculosis
Monitor: baseline & periodic LFTs, TFTs, glucose
Trecator SC (ethionamide) adverse (side) effects
>10%
Disorder of gastrointestinal tract (50%)
Frequency not defined
Postural hypotension
Depression
Dizziness
Drowsiness
Headache
Peripheral neuropathy
Psychosis
Photosensitivity
Rash
Excessive salivation
Gynecomastia
Hypoglycemia
Impotence
Anorexia
Dyspepsia
Diarrhea
Nausea
Metallic taste
Vomiting
Thrombocytopenia
Elevated liver transaminases
Hepatitis
Optic neuritis
Visual changes
Warnings
Contraindications
Hypersensitivity to ethionamide
Severe hepatic dysfunction
Cautions
Use caution in diabetes mellitus, thyroid disease, hepatic impairment
HIV patients may have malabsorption syndrome
Used as monotherapy in the treatment of tuberculosis results in rapid development of resistance; give suitable companion drug or drugs; base the choice on results of susceptibility testing; therapy may be initiated prior to receiving results of susceptibility tests as deemed appropriate by physician; administer with at least one, sometimes two, other drugs to which organism is known to be susceptible
Prescribing drug in the absence of a proven or strongly suspected bacterial infection indication is unlikely to provide benefit to patient and increases risk of development of drug-resistant bacteria
Ethionamide may potentiate adverse effects of other antituberculous drugs administered concomitantly
Perform ophthalmologic examinations (including ophthalmoscopy) before and periodically during therapy
Excessive ethanol ingestion should be avoided; psychotic reaction reported
Pregnancy and lactation
Pregnancy category: C
Lactation: excretion in milk unknown; use with caution
Pregnancy categories
A: Generally acceptable. Controlled studies in pregnant women show no evidence of fetal risk.
B: May be acceptable. Either animal studies show no risk but human studies not available or animal studies showed minor risks and human studies done and showed no risk.
C: Use with caution if benefits outweigh risks. Animal studies show risk and human studies not available or neither animal nor human studies done.
D: Use in LIFE-THREATENING emergencies when no safer drug available. Positive evidence of human fetal risk.
X: Do not use in pregnancy. Risks involved outweigh potential benefits. Safer alternatives exist.
NA: Information not available.
Pharmacology of Trecator SC (ethionamide)
Metabolism: liver
Excretion: kidney
Mechanism of action
Bacteriostatic or bactericidaL
