Drug interactions
Ethinyl estradiol-levonorgestrel + Saquinavir
Severity: Major
Ethinyl estradiol-levonorgestrel and Saquinavir: major interaction.
Last updated
For healthcare professionals — reference only. This page is a brief summary, not medical advice and not a substitute for official labeling or clinical judgement. Always verify before prescribing or dispensing.
Summary
Boosted saquinavir regimens can change estrogen exposure unpredictably and may reduce the reliability of hormonal contraception. Altered hormone levels may also cause adverse effects.
What this interaction means in plain words
Ethinyl estradiol-levonorgestrel and Saquinavir can interact in a way that may be serious. Using them together is sometimes necessary, but it needs a deliberate decision by the prescriber, a plan for monitoring, and clear advice on the warning signs to watch for.
Why it happens
Combined CYP3A4 inhibition and induction of glucuronidation by the ritonavir-boosted regimen alters hormone metabolism.
What to do
Use a non-hormonal contraceptive method or an additional barrier method during saquinavir therapy.
What to ask your pharmacist
- Does the benefit of taking both outweigh the risk in my case?
- Do I need any blood test, ECG or other check while on both?
- What early warning signs should I watch for, and what should I do if they appear?
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Other interactions of Ethinyl estradiol-levonorgestrel
- Ethinyl estradiol-levonorgestrel + Fezolinetant Contraindicated
- Ethinyl estradiol-levonorgestrel + Ombitasvir / paritaprevir / ritonavir and dasabuvir Contraindicated
- Ethinyl estradiol-levonorgestrel + Tranexamic acid Contraindicated
- Aminocaproic acid + Ethinyl estradiol-levonorgestrel Major
- Amobarbital + Ethinyl estradiol-levonorgestrel Major
- Anastrozole + Ethinyl estradiol-levonorgestrel Major
Frequently asked questions
Can I take Ethinyl estradiol-levonorgestrel with Saquinavir?
MediHelp rates the interaction as major. Ethinyl estradiol-levonorgestrel and Saquinavir can interact in a way that may be serious. Using them together is sometimes necessary, but it needs a deliberate decision by the prescriber, a plan for monitoring, and clear advice on the warning signs to watch for. Boosted saquinavir regimens can change estrogen exposure unpredictably and may reduce the reliability of hormonal contraception. Altered hormone levels may also cause adverse effects.
How serious is the interaction between Ethinyl estradiol-levonorgestrel and Saquinavir?
MediHelp rates it major, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Use a non-hormonal contraceptive method or an additional barrier method during saquinavir therapy.
What other medicines interact with Ethinyl estradiol-levonorgestrel?
MediHelp also lists interactions of Ethinyl estradiol-levonorgestrel with, for example, Fezolinetant, Ombitasvir / paritaprevir / ritonavir and dasabuvir, Tranexamic acid. The full list is on the Ethinyl estradiol-levonorgestrel page.
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