ethambutol hydrochloride + isoniazid + pyrazinamide + rifampicin at a glance
Medicine class
Fixed-combination antituberculosis antibiotics
Main use
Initial treatment of tuberculosis under specialist supervision
Food
Take on an empty stomach, before food, as directed by the tuberculosis team
Body fluids
Rifampicin commonly colours urine, sweat, saliva and tears orange-red and can permanently stain soft contact lenses
What is ethambutol hydrochloride + isoniazid + pyrazinamide + rifampicin used for?
This product is licensed for:
Initial treatment of tuberculosis as part of specialist-managed combination therapy.
How does ethambutol hydrochloride + isoniazid + pyrazinamide + rifampicin work?
The components attack tuberculosis bacteria in complementary ways. Rifampicin blocks bacterial RNA production, isoniazid disrupts cell-wall formation, pyrazinamide is particularly active in acidic environments, and ethambutol interferes with multiplication. Combining them improves bacterial killing and helps limit resistant organisms.
How to take ethambutol hydrochloride + isoniazid + pyrazinamide + rifampicin
Follow the tuberculosis team's instructions exactly. Take the tablets by mouth on an empty stomach, before a meal. Do not interrupt or restart treatment independently, because restarting after an interruption may require separate components.
Avoid alcohol because several components can affect the liver.
Tell the team if the large film-coated tablet is difficult to swallow.
Avoid large amounts of tyramine- or histamine-rich foods, such as matured cheese, cured meat and some fish, if they trigger flushing, headache or palpitations.
Check with a pharmacist before using antacids, which can reduce absorption.
ethambutol hydrochloride + isoniazid + pyrazinamide + rifampicin side effects
Common or expected effects
- Orange-red urine, sweat, saliva, sputum and tears
- Nausea, vomiting, reduced appetite or abdominal discomfort
- Headache, dizziness, tiredness or drowsiness
- Itching, flushing, rash or hives
- Tingling or numbness in the hands or feet
- Mild joint or muscle pain
- Raised liver enzymes or uric acid on blood tests
Get urgent medical advice
- Blurred vision, eye pain, altered red-green colour vision or loss of vision
- Hepatitis or liver injury, including jaundice, persistent sickness, severe tiredness or loss of appetite
- Severe skin reactions with blistering, peeling, mouth ulcers, fever or facial swelling
- Severe allergy with breathing difficulty, swelling, collapse or shock
- Unexplained bruising, bleeding or purple skin spots
- Acute kidney injury or markedly reduced urine
- Seizures, severe confusion or psychosis
ethambutol hydrochloride + isoniazid + pyrazinamide + rifampicin in pregnancy
Treatment during pregnancy requires assessment by tuberculosis and maternity specialists; treating serious infection may outweigh potential fetal risks. Rifampicin near delivery may increase maternal or newborn bleeding risk, while isoniazid may prompt pyridoxine supplementation. Do not stop treatment because of pregnancy without specialist advice.
ethambutol hydrochloride + isoniazid + pyrazinamide + rifampicin while breastfeeding
All four components pass into breast milk. Although no adverse effects have been observed in breastfed infants, the product information does not recommend breastfeeding because of a theoretical risk of neurological effects from isoniazid and ethambutol. Discuss feeding options promptly with the specialist team.
ethambutol hydrochloride + isoniazid + pyrazinamide + rifampicin interactions
Rifampicin strongly increases the metabolism of many medicines, while isoniazid can reduce the metabolism of others. A complete interaction review is essential before starting, stopping or changing any medicine.
Hormonal contraceptives
Rifampicin can reduce contraceptive effectiveness; obtain advice about a suitable non-hormonal method.
Warfarin and other coumarin anticoagulants
Anticoagulant effects may change unpredictably, requiring close monitoring and adjustment.
Phenytoin and carbamazepine
Concentrations and effects can change, increasing the risk of treatment failure or toxicity.
Common questions about ethambutol hydrochloride + isoniazid + pyrazinamide + rifampicin
Answers are fully visible for fast scanning and source review.
What is it used for?
It is a fixed combination licensed for initial tuberculosis treatment under specialist supervision.
Should it be taken with food?
Take it on an empty stomach, before food, following the tuberculosis team's instructions.
Why does it turn urine orange?
Sources
These sources were used to prepare and review this medicine page.
Prepared and reviewed by the iatroX editorial team.