Drug interactions
Medroxyprogesterone + Ritonavir
Severity: Moderate
Medroxyprogesterone and Ritonavir: moderate 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
Ritonavir strongly inhibits CYP3A4 and may increase medroxyprogesterone exposure. Increased progestogenic and systemic adverse effects, including Cushingoid effects with prolonged use, have been reported with boosted regimens.
What this interaction means in plain words
Medroxyprogesterone and Ritonavir can affect each other. The combination is often manageable, but it may need a change of dose, a change of timing, or extra checks while both are taken.
Medroxyprogesterone belongs to Endocrine; Ritonavir belongs to Anti Virals.
Why it happens
Ritonavir inhibits CYP3A4, reducing medroxyprogesterone metabolism.
What to do
Monitor for progestin adverse effects and consider dose reduction or an alternative agent for long-term use. Injectable contraception is generally acceptable with ritonavir.
What to ask your pharmacist
- Should I take them at different times of day?
- Does the dose of either medicine need to change?
- Is there anything I should avoid, such as alcohol or certain foods, while on both?
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Other interactions of Medroxyprogesterone
Other interactions of Ritonavir
- Alfuzosin + Ritonavir Contraindicated
- Amiodarone + Ritonavir Contraindicated
- Avanafil + Ritonavir Contraindicated
- Colchicine + Ritonavir Contraindicated
- Dronedarone + Ritonavir Contraindicated
- Eletriptan + Ritonavir Contraindicated
Frequently asked questions
Can I take Medroxyprogesterone with Ritonavir?
MediHelp rates the interaction as moderate. Medroxyprogesterone and Ritonavir can affect each other. The combination is often manageable, but it may need a change of dose, a change of timing, or extra checks while both are taken. Ritonavir strongly inhibits CYP3A4 and may increase medroxyprogesterone exposure. Increased progestogenic and systemic adverse effects, including Cushingoid effects with prolonged use, have been reported with boosted regimens.
How serious is the interaction between Medroxyprogesterone and Ritonavir?
MediHelp rates it moderate, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Monitor for progestin adverse effects and consider dose reduction or an alternative agent for long-term use. Injectable contraception is generally acceptable with ritonavir.
What other medicines interact with Medroxyprogesterone?
MediHelp also lists interactions of Medroxyprogesterone with, for example, Bosentan, Brigatinib, Eslicarbazepine. The full list is on the Medroxyprogesterone page.
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