Dosing & Uses
Dosage Forms & Strengths
tablet
- 250mg
Tuberculosis, Active
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
Dosage Forms & 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
Interactions
Interaction Checker
No Results
Contraindicated
Serious - Use Alternative
Significant - Monitor Closely
Minor
Contraindicated (0)
Serious - Use Alternative (0)
Monitor Closely (3)
- cycloserine
ethionamide, cycloserine. Either increases toxicity of the other by pharmacodynamic synergism. Use Caution/Monitor. Enhanced CNS toxicity; risk of seizure.
- isoniazid
ethionamide increases levels of isoniazid by unspecified interaction mechanism. Use Caution/Monitor.
- sodium picosulfate/magnesium oxide/anhydrous citric acid
ethionamide decreases effects of sodium picosulfate/magnesium oxide/anhydrous citric acid by altering metabolism. Use Caution/Monitor. Coadministration with antibiotics decreases efficacy by altering colonic bacterial flora needed to convert sodium picosulfate to active drug.
Minor (0)
Adverse 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
Postmarketing Reports
Severe cutaneous adverse reactions (SCARs), such as SJS, TEN, DRESS, and AGEP with use of combinations of anti-tuberculosis drugs that included ethionamide
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
Cases of severe cutaneous adverse reactions (SCARs), such as Stevens-Johnson syndrome (SJS), toxic epidermal necrolysis (TEN), drug reaction with eosinophilia and systemic symptoms (DRESS), and acute generalized exanthematous pustulosis (AGEP) reported with use of combinations of anti-tuberculosis drugs that included ethionamide; if symptoms or signs of SCARs develop, discontinue suspect drug(s) immediately and institute appropriate
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 & Lactation
Pregnancy
There are no adequate and well-controlled studies in pregnant women
Effect of therapy on labor and delivery in pregnant women is unknown
Animal data
- Animal studies conducted with this medication indicate that the drug has teratogenic potential in rabbits and rats; doses used in these studies on a mg/kg basis were considerably in excess of those recommended in humans
- Because of these animal studies, however, it must be recommended that therapy be withheld from women who are pregnant, or who are likely to become pregnant while under therapy unless prescribing physician considers it to be an essential part of the treatment
Lactation
- Because no information is available on excretion of ethionamide in human milk, therapy should be administered to nursing mothers only if benefits outweigh risks; newborns who are breast-fed by mothers who are receiving therapy should be monitored for adverse effects
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
Metabolism: liver
Excretion: kidney
Mechanism of Action
Bacteriostatic or bactericidal
Images
Patient Handout
ethionamide oral
ETHIONAMIDE - ORAL
(e-thye-ON-a-mide)
COMMON BRAND NAME(S): Trecator
USES: Ethionamide is used with other medications to treat tuberculosis (TB). Ethionamide is an antibiotic and works by stopping the growth of bacteria.This antibiotic treats only bacterial infections. It will not work for viral infections (such as common cold, flu). Using any antibiotic when it is not needed can cause it to not work for future infections.
HOW TO USE: Take this medication by mouth with or without food as directed by your doctor, usually once daily. If this medication causes stomach upset or nausea/vomiting, take this medication with meals. Also, discuss with your doctor if it may be helpful to divide your daily dose into smaller doses to be taken several times a day. Follow your doctor's instructions carefully.The dosage is based on your age, weight, medical condition, and response to treatment.For the best effect, take this antibiotic at evenly spaced times. To help you remember, take this medication at the same time(s) every day.Continue to take this medication (and other TB medications) until the full prescribed amount is finished, even if symptoms disappear. Stopping the medication too early or skipping doses may result in a return of the infection and cause the infection to be more difficult to treat (resistant).Your doctor may also direct you to take vitamin B6 (pyridoxine) to help prevent certain side effects (such as nerve problems) from ethionamide. Follow your doctor's instructions carefully.Tell your doctor if your condition lasts or gets worse.
SIDE EFFECTS: Nausea, vomiting, diarrhea, abdominal/stomach pain, increased saliva, strange metallic taste in the mouth, loss of appetite, or sores in the mouth may occur. If any of these effects last or get worse, tell your doctor or pharmacist promptly.Many people using this medication may have serious side effects. However, you have been prescribed this drug because your doctor has judged that the benefit to you is greater than the risk of side effects. Careful monitoring by your doctor may decrease your risk.Tell your doctor right away if you have any serious side effects, including: nausea/vomiting that doesn't stop, unusual hunger, unusual sweating, shakiness, unusual tiredness/weakness, yellowing eyes/skin, dark urine, joint pain/swelling, slow heartbeat, mental/mood changes (such as nervousness, restlessness, depression), vision changes (such as blurred/decreased/double vision, color blindness), eye pain, numbness/tingling of arms/legs.A very serious allergic reaction to this drug is rare. However, get medical help right away if you notice any symptoms of a serious allergic reaction, including: fever that doesn't go away, new or worsening lymph node swelling, 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 or at www.fda.gov/medwatch.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: Before taking ethionamide, 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: liver disease, kidney disease, underactive thyroid (hypothyroidism), eye problems (such as optic neuritis, cataracts, diabetic retinopathy).Alcohol may increase the risk of liver disease or mental/mood changes. Avoid alcoholic beverages while using this medication.Ethionamide may cause live bacterial vaccines (such as typhoid vaccine) to not work well. Tell your health care professional that you are using ethionamide before having any immunizations/vaccinations.Before having surgery, tell your doctor or dentist about all the products you use (including prescription drugs, nonprescription drugs, and herbal products).If you have diabetes, this product may lower your blood sugar. Check your blood sugar regularly as directed and share the results with your doctor. Tell your doctor right away if you have symptoms of low blood sugar, such as sudden sweating, shaking, fast heartbeat, hunger, blurred vision, dizziness, or tingling hands/feet. Your doctor may need to adjust your diabetes medication, exercise program, or diet.Tell your doctor if you are pregnant or plan to become pregnant. You should not become pregnant while using ethionamide. Ethionamide may harm an unborn baby. If you become pregnant, talk to your doctor right away about the risks and benefits of this medication.It is unknown if this drug passes into breast milk. Consult your doctor before breast-feeding.
DRUG INTERACTIONS: Drug interactions may change how your medications work or increase your risk for serious side effects. This document does not contain all possible drug interactions. Keep a list of all the products you use (including prescription/nonprescription drugs and herbal products) and share it with your doctor and pharmacist. Do not start, stop, or change the dosage of any medicines without your doctor's approval.
OVERDOSE: If someone has overdosed and has serious symptoms such as passing out or trouble breathing, call 911. Otherwise, call a poison control center right away. US residents can call their local poison control center at 1-800-222-1222. Canada residents can call a provincial poison control center.
NOTES: Do not share this medication with others.Lab and/or medical tests (such as sputum test, eye/vision exams, liver/thyroid function, blood glucose, complete blood count) should be done while you are taking this medication. Keep all medical and lab appointments. Consult your doctor for more details.
MISSED DOSE: It is important to take each dose of this medication as scheduled. If you miss a dose, take it as soon as you remember. If it is near the time of the next dose, skip the missed dose. Take your next dose at the regular time. Do not double the dose to catch up.
STORAGE: Store at room temperature away from light and moisture. Do not store in the bathroom. Keep all medications away from children and pets.Do not flush medications down the toilet or pour them into a drain unless instructed to do so. Properly discard this product when it is expired or no longer needed. Consult your pharmacist or local waste disposal company.
Information last revised September 2023. Copyright(c) 2023 First Databank, Inc.
IMPORTANT: HOW TO USE THIS INFORMATION: This is a summary and does NOT have all possible information about this product. This information does not assure that this product is safe, effective, or appropriate for you. This information is not individual medical advice and does not substitute for the advice of your health care professional. Always ask your health care professional for complete information about this product and your specific health needs.
Formulary
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