| Interaction Color Code | Clinical Bottom Line | Clinical Effects | Drug 1 effect | Drug 2 dose | Drug 2 effect | Management | |
|---|---|---|---|---|---|---|---|
| Nevirapine LNG 619 | Red: Avoid combination | Do not coadminister: Reduced levels of levonorgestrel | Levonorgestrel AUC increased 35% |
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| Efavirenz LNG 451 | Red: Avoid combination | Do not coadminister: Reduced levels of levonorgestrel | Decreased levonorgestrel effects |
0.75 mg x 1 | Levonorgestrel AUC decreased 64%; Cmax decreased 45%; Cmin decreased 71%; half-life: decreased 47% |
Use alternative contraceptive method |
|
| Cabotegravir LNG 330 | Green: Administer standard doses | Administer standard doses | Not studied |
0.15 mg once daily | Cmax increased 5%, AUC increased 12%, Cmin increased 7% |
||
| Elvitegravir LNG 221 | Orange: Minimal data to guide interaction | Minimal data to guide interaction: risks likely to outweigh benefits | Potential increase in levonorgestrel adverse effects |
Additional or alternative contraception should be considered. |
