Drug interactions
Dexamethasone-neomycin-polymyxin + Nirmatrelvir
Severity: Moderate
Dexamethasone-neomycin-polymyxin and Nirmatrelvir: 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
Nirmatrelvir is a CYP3A4 inhibitor and, boosted with ritonavir, can markedly raise systemic dexamethasone levels. Over longer use this may cause Cushing syndrome and adrenal suppression. Topical use for a short duration carries little systemic exposure.
What this interaction means in plain words
Dexamethasone-neomycin-polymyxin and Nirmatrelvir 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.
Dexamethasone-neomycin-polymyxin belongs to Anti Bacterial; Nirmatrelvir belongs to Anti Virals.
Why it happens
Nirmatrelvir inhibits CYP3A4, decreasing dexamethasone metabolism.
What to do
For a 5-day antiviral course with topical use, no change is needed. With systemic dexamethasone, consider an alternative such as prednisolone or monitor closely for steroid excess.
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?
Pro+ members
Unlock the full page
Create an account and start a Pro+ trial to unlock the full management advice for Dexamethasone-neomycin-polymyxin and Nirmatrelvir, the additional notes, the evidence detail and the whole-prescription interaction checker.
- Full clinical management advice
- Additional notes
- Evidence detail
- Interaction checker for a whole prescription
Try Pro+ free for 7 days on the web. No card needed.
Other interactions of Dexamethasone-neomycin-polymyxin
- Dexamethasone-neomycin-polymyxin + Ketorolac Major
- Dexamethasone-neomycin-polymyxin + Lapatinib Major
- Dexamethasone-neomycin-polymyxin + Levofloxacin Major
- Dexamethasone-neomycin-polymyxin + Mifepristone Major
- Dexamethasone-neomycin-polymyxin + Moxifloxacin Major
- Aldesleukin + Dexamethasone-neomycin-polymyxin Moderate
Other interactions of Nirmatrelvir
- Alfuzosin + Nirmatrelvir Contraindicated
- Amiodarone + Nirmatrelvir Contraindicated
- Apalutamide + Nirmatrelvir Contraindicated
- Carbamazepine + Nirmatrelvir Contraindicated
- Colchicine + Nirmatrelvir Contraindicated
- Dronedarone + Nirmatrelvir Contraindicated
Frequently asked questions
Can I take Dexamethasone-neomycin-polymyxin with Nirmatrelvir?
MediHelp rates the interaction as moderate. Dexamethasone-neomycin-polymyxin and Nirmatrelvir 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. Nirmatrelvir is a CYP3A4 inhibitor and, boosted with ritonavir, can markedly raise systemic dexamethasone levels. Over longer use this may cause Cushing syndrome and adrenal suppression. Topical use for a short duration carries little systemic exposure.
How serious is the interaction between Dexamethasone-neomycin-polymyxin and Nirmatrelvir?
MediHelp rates it moderate, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: For a 5-day antiviral course with topical use, no change is needed. With systemic dexamethasone, consider an alternative such as prednisolone or monitor closely for steroid excess.
What other medicines interact with Dexamethasone-neomycin-polymyxin?
MediHelp also lists interactions of Dexamethasone-neomycin-polymyxin with, for example, Ketorolac, Lapatinib, Levofloxacin. The full list is on the Dexamethasone-neomycin-polymyxin page.
Full monographs, dosing and an interaction checker in the MediHelp app
Open the complete reference, check multi-drug interactions and use dosing tools in the MediHelp app.
