drugs which have potential to effect the efficacy of hormonal contraception
Last reviewed 01/2018
Example drugs are listed. Please check guidance (1) and BNF for more comprehensive information.
- drugs that reduce contraceptive hormone levels or decrease contraceptive
effects are
- antiepileptics e.g. - carbamazepine, phenobarbital, phenytoin
- modest to marked reduction in ethinylestradiol (EE) and progestogens.
Possible reduced contraceptive efficacy
- modest to marked reduction in ethinylestradiol (EE) and progestogens.
Possible reduced contraceptive efficacy
- antibiotics e.g. - rifabutin, rifampicin
- rifabutin associated with a modest reduction in EE or estradiol
and progestogen. Rifampicin has a marked effect
- rifabutin associated with a modest reduction in EE or estradiol
and progestogen. Rifampicin has a marked effect
- antiretroviral e.g. - ritonavir - marked reduction in EE. EE reduced
by 40%. Additional and/or alternative contraceptive methods advised
- emergencey contraceptives e.g - ulipristal acetate
- theoretical reduction in the efficacy of progestogen-containing
contraceptives. Additional precautions required for 14 days (9 days
if using or starting POP, 16 days for Qlaira®)
- theoretical reduction in the efficacy of progestogen-containing
contraceptives. Additional precautions required for 14 days (9 days
if using or starting POP, 16 days for Qlaira®)
- gastrointestinal drugs e.g. - proton pump inhibitors, antacids, H2 receptor
antagonists
- theoretical reduction in plasma concentrations of UPA and may result
in decreased efficacy. Concomitant use not recommended
- theoretical reduction in plasma concentrations of UPA and may result
in decreased efficacy. Concomitant use not recommended
- herbal e.g. - St. Johns Wort - is a weak enzyme inducer and has the
potential to reduce efficacy
- antiepileptics e.g. - carbamazepine, phenobarbital, phenytoin
- drugs that increase contraceptive hormone levels
- antibacterial e.g. - erythromycin
- antibacterial e.g. - erythromycin
- the clinical significance is not known but increased adverse events might
be anticipated
- antifungal e.g. - fluconazole, itraconazole, ketoconazole
- antifungal e.g. - fluconazole, itraconazole, ketoconazole
- modest increases in EE and progestogen
- antiretroviral e.g. - atazanavir
- NSAID's e.g. - etoricoxib
- doses of etoricoxib >=60 mg raise ethinylestradiol (EE) levels
by approximately 40% or more
- doses of etoricoxib >=60 mg raise ethinylestradiol (EE) levels
by approximately 40% or more
- potential risk of estrogen-related adverse events
- statins e.g - atorvastatin the clinical significance is not known but likely to be small
Reference