Rifampicin + Isoniazid
Also sold as: Rifinah
Prescription neededTB medicines
Comes as:Tablet
Usual adult dose
Dose is set by your doctor. The number of tablets depends on body weight; taken once a day on an empty stomach, usually in the last 4 months of TB treatment. Never stop TB treatment early.
Your doctor may give you a different dose. Children's doses depend on weight.
Side effects
Common
- orange-red urine and tears (harmless)
- nausea
- loss of appetite
- tingling of hands or feet
Serious — get help
Stop taking it and see a doctor straight away if you notice:
- yellow eyes or skin
- dark urine
- severe vomiting or stomach pain
- unusual bleeding
- severe skin rash
Do not take it, or take care, if
- Jaundice or active liver disease
- Allergy to rifampicin or isoniazid
- Hormonal birth control pills and injections work less well — use another method
- Taking HIV medicines or warfarin (doctor must adjust)
Interactions
Medicines that can react with this one.
Serious2 medicinesDo not take these together unless your doctor says so.
- Ethinylestradiol + Levonorgestrel
Rifampicin makes the pill unreliable; use another method of contraception.
- Warfarin
Rifampicin strongly lowers the effect of warfarin; INR must be checked closely.
Moderate1 medicineTake together only with care. Ask your doctor or pharmacist.
- Phenytoin
Phenytoin levels can change in either direction; levels should be checked.