recent report suggesting that efavirenz decreases the efficacy of intradermal Jadelle implant (this is the successor to Norplant, with 2 thin, flexible silicone rods, each containing 75 mg of the synthetic progestin levonorgestrel).
here is the abstract (that is all i could find), from PubMed:
Perry SH, Swamy P, Preidis GA, Mwanyumba A, Motsa N, Sarero HN. AIDS. 2014 Jan 2. [Epub ahead of print] Implementing the Jadelle implant for women living with HIV in a resource-limited setting in sub-Saharan Africa: concerns for drug interactions leading to unintended pregnancies.
“An analysis of 570 HIV-infected women in Swaziland using the Jadelle implant showed that age, condom use, which provider placed the implant, and CD4 cell count had no effect on unintentional pregnancy rates. However, antiretroviral regimen at the time of pregnancy correlated with pregnancy outcomes (P <0.001). None of the women on nevirapine or lopinavir/ritonavir-based regimens (n = 208 and 13, respectively) became pregnant, whereas 15 women on efavirenz (n = 121; 12.4%) became pregnant.”
so, this is a double hit for efavirenz. there are reports that HIV regimens with efavirenz lead to lower progestin blood levels on women on combination oral contraceptives (and recommendations that condoms still be used for contraception, as well as prevention of sexually-transmitted diseases). this report adds significantly to the prior concerns. in addition, efavirenz is probably the most teratogenic of the HIV antiretrovirals. so, bottom line, prob best not to choose efavirenz-based therapy on women of child-bearing age…
geoff