|
| Antiretroviral (ARV) drug | Effect on drug levels | Dosing recommendation/clinical comment |
|
| Nonnucleoside reverse transcriptase inhibitor (NNRTI) |
|
| | Oral ethinyl estradiol/norgestimate No effect on ethinyl estradiol concentrations: ↓ active metabolites of norgestimate (levonorgestrel AUC ↓83%; norelgestromin AUC ↓64%) | A reliable method of barrier contraception must be used in addition to hormonal contraceptives. EFV had no effect on ethinyl estradiol concentrations, but progestin levels (norelgestromin and levonorgestrel) were markedly decreased. No effect of ethinyl estradiol/norgestimate on EFV plasma concentrations was observed. |
| Efavirenz (EFV) | Implant: ↓ etonogestrel | A reliable method of barrier contraception must be used in addition to hormonal contraceptives. The interaction between etonogestrel and EFV has not been studied. Decreased exposure of etonogestrel may be expected. There have been postmarketing reports of contraceptive failure with etonogestrel in EFV-exposed patients. |
| | Levonorgestrel AUC ↓ 58% | Effectiveness of emergency postcoital contraception may be diminished |
| Etravirine (ETR) | Ethinyl estradiol AUC ↑ 22%
Norethindrone: no significant effect | No dosage adjustment necessary |
| Nevirapine (NVP) | Ethinyl estradiol AUC ↓ 20%
Norethindrone AUC ↓ 19% | Use alternative or additional methods
|
| DMPA: no significant change | No dosage adjustment needed |
|
| Ritonavir-(RTV-) boosted protease inhibitor (PI) |
|
| Atazanavir/ritonavir (ATV/r) | ↓ Ethinyl estradiol
↑ Norgestimate | Oral contraceptive should contain at least 35 mcg of ethinyl estradiol. Oral contraceptives containing progestins other than norethindrone or norgestimate have not been studied |
| Darunavir/ritonavir (DRV/r) | Ethinyl estradiol AUC ↓ 44%
Norethindrone AUC ↓ 14% | Use alternative or additional method |
| Fosamprenavir/ritonavir (FPV/r) | Ethinyl estradiol AUC ↓ 37%
Norethindrone AUC ↓ 34% | Use alternative or additional method |
| Lopinavir/ritonavir (LPV/r) | Ethinyl estradiol AUC ↓ 42%
Norethindrone AUC ↓ 17% | Use alternative or additional method |
| Saquinavir/ritonavir (SQV/r) | ↓ Ethinyl estradiol | Use alternative or additional method |
| Tipranavir/ritonavir (TPV/r) | Ethinyl estradiol AUC ↓ 48%
Norethindrone: No significant change | Use alternative or additional method |
|
| PI without RTV |
|
| Atazanavir (ATV) | Ethinyl estradiol AUC ↑ 48%
Norethindrone AUC ↑ 110% | Oral contraceptive should contain no more than 30 mcg of ethinyl estradiol or use alternative method. Oral contraceptives containing less than 25 mcg of ethinyl estradiol or progestins other than norethindrone or norgestimate have not been studied |
| Fosamprenavir (FPV) | With APV: ↑ ethinyl estradiol and ↑ norethindrone; ↓ APV 20% | Use alternative method |
| Indinavir (IDV) | Ethinyl estradiol AUC ↑ 25%
Norethindrone AUC ↑ 26% | No dose adjustment |
| Nelfinavir (NFV) | Ethinyl estradiol AUC ↓ 47%
Norethindrone AUC ↓ 18% | Use alternative or additional method |
|
| CCR5 antagonist |
|
| Maraviroc (MVC) | No significant effect on ethinyl estradiol or levonorgestrel | Safe to use in combination |
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