Question

A 30-year-old woman on the combined oral contraceptive pill (COC) is prescribed rifampicin for tuberculosis. According to the BNF, what effect does rifampicin have on COC?

Accepted Answer

Rifampicin reduces the efficacy of COC due to enzyme induction

Answer

No interaction

Answer

Rifampicin increases COC levels

Answer

Rifampicin changes the COC half-life but no clinical impact

Answer

Rifampicin and COC are synergistic

Practice question

A 30-year-old woman on the combined oral contraceptive pill (COC) is prescribed rifampicin for tuberculosis. According to the BNF, what effect does rifampicin have on COC?