Levonorgestrel-containing emergency hormonal contraception: advice on interactions with hepatic enzyme inducers and contraceptive efficacy
Medicines or herbal remedies that induce CYP3A4 enzymes reduce blood levels of levonorgestrel, which may reduce emergency contraceptive efficacy.
Switching from posaconazole oral solution to tablets has resulted in cases of dose-related toxicity, whereas switching from tablets to oral solution has resulted in underdosing and lack of efficacy.
Updated advice for healthcare professionals is available, after conclusion of a review of the safety of idelalisib, including the risk of infection.
A summary of safety letters sent to healthcare professionals in August 2016