rifampicin: clinical use

Prescribing considerations

• Use under an appropriately qualified clinician and combine with other active agents when required to prevent resistance.
• Complete medication reconciliation before initiation and again at discontinuation because induction affects many therapeutic classes.
• Avoid unplanned treatment interruption; obtain specialist advice before restarting after a significant gap.
• Exercise particular caution with existing liver dysfunction, older patients with liver impairment and patients at increased bleeding risk.
• Reserve intravenous use for patients unable to receive or absorb oral therapy, transferring to an oral formulation when clinically suitable.

Contraindications and cautions

• Hypersensitivity to rifampicin, another rifamycin or a formulation excipient.
• Jaundice is a contraindication to the selected oral products; intravenous use is not recommended without careful benefit-risk assessment.
• Concurrent saquinavir with ritonavir.
• Concurrent lurasidone or specified highly induction-sensitive antivirals, including sofosbuvir, cabotegravir, fostemsavir and lenacapavir; product-specific lists also include daclatasvir and telaprevir.

Monitoring

• For tuberculosis, obtain pretreatment liver-function tests; in adults also assess bilirubin, creatinine, full blood count and platelets.
• Review regularly for adverse-reaction symptoms; repeat laboratory tests when baseline results are abnormal or symptoms develop.
• Use closer liver monitoring in hepatic impairment or other high-risk circumstances.
• Monitor coagulation where vitamin K deficiency, hypoprothrombinaemia or another bleeding risk is present.
• Plan therapeutic, biochemical or clinical monitoring for interacting medicines when rifampicin is started or stopped.

Clinical pharmacology

Rifampicin is bactericidal through selective inhibition of bacterial DNA-dependent RNA polymerase. Oral absorption is reduced by food; it distributes widely, undergoes biliary elimination and enterohepatic cycling, and is a potent inducer of CYP enzymes, conjugation pathways and transporters.

Formulation and product differences

• The selected hard capsules contain lactose; the selected capsule presentation also contains a trace of azorubine.
• The selected raspberry-flavoured oral suspension contains sucrose, sodium metabisulphite and a small amount of ethanol; it should not be diluted.
• The infusion is a lyophilised intravenous preparation supplied with solvent and is intended for patients unable to receive or absorb oral treatment.

Capsule

Route: Oral

Strengths: 150 mg, 300 mg

Oral suspension

Route: Oral

Strengths: 100 mg/5 mL