Ethionamide (oral)

Ethionamide is an antibiotic treatment that is used in conjunction with other treatments to kill the tuberculosis bacteria.


Ethionamide is a medication that can either be used alone or together with other treatments in patients suffering from the bacterial infection tuberculosis.

Tuberculosis is a disease caused by a bacterial infection that will normally effect the lungs, but which can cause damage in other areas of the body too. TB can be deadly if untreated, but the condition can be cured through the use of medications like Ethionamide.

Ethionamide will not be effective against viral infections such as colds or flu and should not be used in their treatment.

This medication is available only when prescribed by a doctor and is taken in tablet form.

The treatment is prescribed as either Trecator or Trecator-SC tablets.

Condition treated

  • Tuberculosis (TB)

Type Of Medicine

  • Antibiotic

Side Effects

The use of Ethionamide can cause unwanted side effects in the patient as well as having the desired effect of killing the bacterial infection. Not all of the following side effects may occur, but in some cases they may require that you seek urgent medical attention. Before taking this treatment you should familiarize yourself with the potential side effects and understand how to react if they occur.

You should contact your doctor immediately if you are experiencing any of the following side effects from the use of Ethionamide:

Occurring less commonly:

  • Clumsiness
  • Confusion or disorientation
  • Mental depression or extreme sadness
  • Numbness, tingling or burning pains in the hands and/or feet
  • Unsteadiness
  • Yellowing of the eyes
  • Yellowing of the skin

Occurring only rarely:

  • Blindness
  • Blurring of vision or loss of quality of vision
  • Burning or tingling feelings of the skin
  • Changed menstrual periods
  • Changes to vision
  • Coldness when warm
  • Decrease in sexual ability occurring in males
  • Decreased vision
  • Development of color blindness to blue and/or yellow
  • Difficulty concentrating on tasks
  • Dry or puffy skin
  • Eye pain
  • Feverishness
  • Hives
  • Hoarseness
  • Increased heart rate
  • Increase in hunger
  • Increase in sensitivity of the skin to UV rays
  • Irritation
  • Itching
  • Joint pain
  • Rash
  • Reddening or other discoloration of the skin
  • Severe sunburn
  • Shakiness or trembling
  • Stiffness of the joints
  • Swelling of the front part of the neck
  • Swelling of the joints
  • Swollen eyelids, face, lips, hands or feet
  • Tightness across the chest
  • Troubled breathing
  • Troubled swallowing
  • Weakness experienced in the hands or feet
  • Weight increase

Frequency of incidence not known:

  • Chills when warm
  • Cold sweats
  • Coma
  • Cool and unusually pale skin
  • Darkened urine
  • Dizziness
  • General tiredness
  • General weakness
  • Headache
  • Lightened coloration of stools
  • Nausea
  • Nightmares
  • Pain in the upper right abdomen
  • Seizures or convulsions
  • Slurring of speech
  • Stomach pain
  • Unusual tiredness
  • Unusual weakness
  • Vomiting
  • Yellowing of the eyes
  • Yellowing of the skin

Other side effects can also occur that would not normally necessitate that you visit a doctor. These side effects are usually mild and will often abate over time as your body becomes used to the treatment. You should check with your healthcare professional if these side effects become bothersome or are ongoing, but the following would not normally necessitate a visit to your doctor:

Occurring more commonly:

  • Abdominal pains
  • Diarrhea
  • Increased production of saliva
  • Lack of appetite
  • Metallic taste in mouth
  • Stomach pain
  • Swelling or inflammation in and around the mouth
  • Weight loss

Frequency of incidence not known:

  • Blemishes appearing on the skin
  • Decreased interest in having sexual intercourse
  • Enlargement of the breasts occurring in males
  • Inability to get or to maintain an erection
  • Loss of sexual ability or performance
  • Loss of sexual drive or desire
  • Pimples

Other side effects that have not been listed herein may also occur. If you experience other side effects then you should contact your physician. If you feel that your immediate health is at risk, however, then you should always contact the emergency services.


This medication should only be taken as and when directed by your doctor. You should never take a greater dose, use the treatment for longer than prescribed, nor take it more frequently than prescribed by your doctor. Taking increased doses of this treatment will expose you to greater risks and greater severity of side effects.

Some patients may experience stomach discomfort from the use of this treatment. In this case you should take it after meals to alleviate this side effect.

This medication needs to be taken for the entirety of its term. TB and the symptoms of TB may abate before the treatment is finished but bacteria may still remain. Stopping treatment early exposes the patient to the risk of the bacterial infection returning. To ensure that TB is completely killed and cannot return your doctor may direct you to take this treatment for 1-2 years after the symptoms of the infection have abated. This is because the tuberculosis bacteria is very resilient and it is essential that it is properly killed.

Your doctor may also prescribe other treatments such as pyridoxine to lessen the side effects that can occur from the use of Ethionamide. Where other medications are also prescribed it is essential that you take both treatments as directed and do not miss any doses of either treatment.

The prescribed dose of this treatment will vary between patients depending on a range of different factors. The amount prescribed will depend on the strength of the medication prescribed, the number of doses taken each day, the time between doses and the period of time for which you will be taking the treatment. You should not change the dose you are taking at any point unless directed to by your doctor. The following information is a guideline only and you should use your treatment as directed by the prescribing doctor.

For treatment of tuberculosis with Ethionamide tablets:

In adults

  • Dose is based on the body weight of the patient and should be calculated by the prescribing doctor.
  • The initial dose given is usually 250mg taken once daily. This may be increased by your doctor for best effect.
  • The dose given should not normally exceed 100mg taken daily.

In children aged 12+

  • The dose in each case will be based on the body weight of the patient and will be calculated by the prescribing doctor.
  • The starting dose is normally 10-20mg/kg taken daily. This dose should be divided into 2-3 doses and taken after meals.

In children aged below 12

  • Use in children aged 12 or younger is not recommended.

If a dose of this treatment is missed then you should take it as soon as you are able to. If it is time for your next dose, however, then you should skip the missed dose completely and return to your usual schedule. Do not ever take a double dose of this treatment.


Certain medications should not be used together as they can interact in the body and cause severe side effects. In the worst cases medications can cause life-threatening conditions when used in conjunction with one another. In other cases medications may stop one another from working or may increase the risk or severity of certain side effects.

Before beginning use of this treatment you should inform your doctor of all other treatments that you are receiving. This includes prescribed medications, over the counter treatments you have purchased or other herbal remedies and vitamin supplements that you take. It is especially important that you inform your doctor if you are using any of the following medications.

The use of these medications in conjunction with Ethionamide is not normally recommended but in some cases it may be required. If both medications are prescribed then your doctor may need to change the dose or frequency of use of one or both of the treatments.

  • Pyrazinamide
  • Rifampin

Interactions with other medications may also occur. You should ensure that you inform your doctor of all treatments you are taking even if they are not listed here.

Other medical problems may also limit the use of this treatment. You should inform your doctor of your full medical history before you begin treatment with this medication. This is especially important if you suffer from any of the following conditions

The following conditions may be worsened by the use of Ethionamide:

  • Diabetes
  • Thyroid problems

Patients suffering with the following should not be treated with Ethionamide:

Other medical conditions not listed here may also impact the safe and effective use of Ethionamide. Ensure that you inform your doctor of all medical conditions from which you suffer before beginning treatment.


Before deciding to take any medication it is essential that you weigh the benefits of doing so against the risks that you face from use. Ensure that you understand the potential side effects of use and ensure that you are not taking any other treatments that may affect the use of Ethionamide before beginning treatment. You should also ensure that you have taken all of the following into account with your doctor:

Allergies ' You should inform your doctor if in the past you have had an allergic reaction to any medication as this my prohibit use in some cases. You should also inform your doctor of any other allergies from which you may suffer.

Pediatic ' Ethionamide is not recommended for use in children below the age of 12.

Geriatric ' There are no known limitations to the use of this treatment in elderly patients. Elderly patients are more likely to have conditions that may impact the use of this treatment.

Pregnancy' You should inform your doctor before use if you are currently pregnant or if you believe that you may get pregnant during use of this treatment. There is a risk associated to the use of this treatment during pregnancy and you should discuss this with your doctor.

Breastfeeding ' Discuss the potential risks of breastfeeding an infant with your doctor before beginning use of this treatment.

During use of this treatment your doctor will need to check up on your progress regularly. Blood and urine tests may be required to determine the occurrence of any unwanted side effects.

Patients should avoid consumption of alcohol during use of this treatment.

Patients taking this treatment should consult their doctor if they do not begin to experience positive health improvements within 2-3 weeks.

Ethionamide may affect your vision and you should assess this before you drive or operate machinery. Ensure that you understand how the treatment affects you before you carry out any activities that may put you or others at risk if your eyesight is affected.

Do not take any other medications in conjunction with this treatment without first discussing this with your doctor.


This medication should be stored at room temperature in a closed container. Keep it away from light, moisture and heat.

Always keep medications out of the reach of children.

You should dispose of unwanted or outdated medication as soon as possible and as directed by your doctor.


Ethionamide is an antibiotic treatment that helps to fight the bacterial infection of tuberculosis in patients. It can be taken in isolation or in conjunction with certain other medications to treat patients.

Ethionamide kills the bacterial infection of tuberculosis. Positive health improvements should be seen within 2-3 weeks but the patient may need to continue use of this treatment for 1-2 years in order to fully and completely cure TB.