Letermovir Injection and Benzhydrocodone: Interaction Details
AI-assisted, pharmacist-reviewed · Source data updated Aug 8, 2026 · Sources: FDA labeling, DDInter 2.0, cited literature
Benzhydrocodone
No brand names on recordLetermovir Injection
How we grade severity & evidence
Severity levels
- Contraindicated: These should generally not be used together.
- Major: Potentially serious — often needs a change or close monitoring.
- Moderate: Can be significant — usually manageable with monitoring.
- Minor: Usually limited clinical impact.
Evidence grades
- Established: Well documented — supported by controlled studies or strong clinical data.
- Probable: Good supporting evidence, though not definitively proven.
- Suspected: Some evidence suggests this interaction, but it is not well established.
- Possible: Limited or conflicting evidence; the interaction may occur.
- Theoretical: Predicted from the drugs' pharmacology; not yet confirmed in people.
Ratings come from the documented interaction literature and are reviewed by a pharmacist. They describe the documented risk of the combination, not what will necessarily happen to you — your dose, timing, and health picture all matter.
What happens
Increased HYDROcodone exposure and risk of increased or prolonged opioid effects
Interaction Deep Dive
Coadministration of HYDROcodone, a CYP3A4 substrate, with any CYP3A4 inhibitor may increase the plasma concentration of HYDROcodone and the risk of opioid toxicity. These effects could be more pronounced with concomitant use of HYDROcodone and CYP3A4 and CYP2D6 inhibitors, particularly when an inhibitor is added after a stable dose of HYDROcodone is achieved. After stopping a CYP3A4 inhibitor, as the effects of the inhibitor decline, the HYDROcodone plasma concentration will decrease, resulting in decreased opioid efficacy or a withdrawal syndrome in patients who had developed physical dependence to HYDROcodone. If concomitant use is required, frequently monitor patients for respiratory depression or sedation and consider dose reduction of HYDROcodone. If a CYP3A4 inhibitor is discontinued, consider increasing the HYDROcodone dosage until stable drug effects are achieved. Monitor for signs of opioid withdrawal1234.
Why it happens (mechanism)
Inhibition of CYP3A4-mediated metabolism of HYDROcodone
Literature reports
1 report — tap to read
a) Coadministration of HYDROcodone (20 mg single dose) and CYP3A4 inhibitor ketoconazole (200 mg BID for 6 days) increased mean HYDROcodone AUC and Cmax by 135% and 78%, respectively 3.
Common questions
Can I take Letermovir Injection and Benzhydrocodone together?
Increased HYDROcodone exposure and risk of increased or prolonged opioid effects Always confirm with your pharmacist or prescriber before making any change.
How serious is the Letermovir Injection and Benzhydrocodone interaction?
It is rated major. Potentially serious — often needs a change or close monitoring.
How quickly could this interaction happen?
The documented onset is "unspecified". The timing of this interaction is not well characterized.
How strong is the evidence for this interaction?
The evidence is graded "probable". Good supporting evidence, though not definitively proven.
Questions for your pharmacist
- Does my dose of Letermovir Injection or Benzhydrocodone need adjusting while I take them together?
- What symptoms should prompt me to call you or my prescriber right away?
- Does the timing of my doses matter for this combination?
- Is there a safer alternative to one of these medications for me?
References (4)
- Product Information: VANTRELA(TM) ER oral extended-release tablets, hydrocodone bitartrate oral extended-release tablets. Teva Pharmaceuticals USA, Inc (per manufacturer), North Wales, PA, 2017. DailyMed
- Product Information: ZOHYDRO(R) ER oral extended-release capsules, hydrocodone bitartrate oral extended-release capsules. Currax Pharmaceuticals LLC (per FDA), Morristown, NJ, 2021. DailyMed
- Product Information: HYSINGLA(R) ER oral extended-release tablets, hydrocodone bitartrate oral extended-release tablets. Purdue Pharma LP (per FDA), Stamford, CT, 2023. DailyMed
- Product Information: APADAZ(R) oral tablets, benzhydrocodone acetaminophen oral tablets. Zevra Therapeutics, Inc. (per FDA), Celebration, FL, 2023. DailyMed
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