Rifampicin: what it does and what to watch

Also known as: Rifamycin antibiotic, Anti-tuberculosis medicine · Antibiotic (rifamycin), used in tuberculosis and certain other infections · Updated 2026-08-20 · Educational — not medical advice

Illustrative — the liver, monitored during tuberculosis treatment

In plain language: This medicine blocks a bacterial enzyme called RNA polymerase, which bacteria need to copy their genetic instructions into RNA in order to make proteins and multiply. Without this step bacterial growth halts. For tuberculosis it is almost always given together with other antibiotics, since using it alone allows resistant bacteria to survive and multiply.

What it's used for

  • Treatment of tuberculosis as part of combination therapy
  • Prevention of meningococcal disease in close contacts of a case
  • Treatment of certain other bacterial infections in combination with other antibiotics

Common side effects

  • Orange-red discolouration of urine, tears, sweat, and saliva
  • Nausea
  • Stomach upset
  • Headache
  • Flushing

Get medical help if…

Liver inflammation, which can occasionally be serious, especially with alcohol use or other liver-affecting medicines

Flu-like reactions with fever and chills, more likely with irregular or interrupted dosing

Rare serious skin reactions or drops in blood counts

Lab values it can move

Few guides tell you this part: medicines show up in blood work. If you take Rifampicin and a value below looks off on your report, this may be part of the story — never stop a medicine without your doctor.

Liver enzymes are checked before starting and periodically during treatment, since this medicine can cause liver inflammation that is usually mild but occasionally significant.

SGPT (ALT)

This enzyme is monitored alongside ALT as part of routine liver function checks throughout treatment.

SGOT (AST)

A rise in bilirubin can signal more significant liver involvement and is checked if liver enzymes are also elevated.

Total Bilirubin

Good to know

  • This medicine is a potent liver-enzyme inducer, meaning it speeds up how quickly the body breaks down many other medicines, including hormonal contraceptives, so additional or alternative contraception is usually needed
  • The orange-red tint to urine, tears, sweat, and saliva is expected and harmless, but soft contact lenses may become permanently stained
  • Liver function is checked periodically, especially during the first months of treatment
  • Report any yellowing of the eyes or skin, unusual tiredness, or loss of appetite promptly
  • Tell every prescriber about this medicine, since it interacts with many others, including some antivirals, blood thinners, and hormonal medicines

Questions people ask

Should I be worried that my urine and tears have turned orange?

No, this is an expected and harmless effect of the medicine's own colour passing through body fluids, including urine, tears, sweat, and saliva. It is worth knowing about in advance so it doesn't cause alarm, though it can permanently stain soft contact lenses and light-coloured clothing, so some people switch to glasses during treatment.

Why do I need extra contraception while taking this medicine?

This medicine strongly induces liver enzymes that break down many other drugs faster than usual, including the hormones in contraceptive pills, patches, and some other hormonal methods, making them less reliable. Using an additional or alternative, non-hormonal method of contraception during treatment and for some time afterward is generally recommended to avoid an unintended pregnancy.

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