Drug Interaction Report

Codeine and Dexamethasone Ophthalmic: Interaction Details

AI-assisted, pharmacist-reviewed · Source data updated Aug 8, 2026 · Sources: FDA labeling, DDInter 2.0, cited literature

Codeine

Tuzistra XR® (as a combination product containing Chlorpheniramine, Codeine)
+

Dexamethasone Ophthalmic

Dexacidin® (as a combination product containing Dexamethasone, Neomycin, Polymyxin B) Dexair Dexasporin® (as a combination product containing Dexamethasone, Neomycin, Polymyxin B) Maxidex® Maxitrol® (as a combination product containing Dexamethasone, Neomycin, Polymyxin B) Neodecadron® (as a combination product containing Dexamethasone, Neomycin) TobraDex® (as a combination product containing Dexamethasone, Tobramycin)
Dr. Brian Staiger, PharmD, BCPS
Medically reviewed by
Updated Aug 8, 2026
LinkedIn
Interaction severity
Major
Potentially serious — often needs a change or close monitoring.
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.

Of 55 documented Codeine interactions, 52 are rated major — including this one.
Worried about symptoms right now? Contact your pharmacist or prescriber, or call Poison Control at 1-800-222-1222 (US). Call 911 for an emergency.
Onset
unspecified
Evidence
theoretical
Severity
Major

What happens

Reduced codeine and morphine exposure, reduced opioid efficacy and precipitation of opioid withdrawal

Interaction Deep Dive

Concomitant use of codeine with CYP3A4 inducers may result in reduced codeine levels, greater norcodeine levels, and less metabolism via CYP2D6 with resultant lower morphine levels, resulting in decreased efficacy or onset of a withdrawal syndrome in patients who have developed physical dependence. If concomitant use is needed, closely monitor patients for decreased efficacy or signs of opioid withdrawal syndrome, and consider increasing the dose of codeine as necessary. If a CYP3A4 inducer is being discontinued, consider codeine dose reduction and closely monitor patients for signs of respiratory depression or sedation12.

Why it happens (mechanism)

Induction of CYP3A4-mediated codeine metabolism

Common questions

Can I take Codeine and Dexamethasone Ophthalmic together?

Reduced codeine and morphine exposure, reduced opioid efficacy and precipitation of opioid withdrawal Always confirm with your pharmacist or prescriber before making any change.

How serious is the Codeine and Dexamethasone Ophthalmic 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 "theoretical". Predicted from the drugs' pharmacology; not yet confirmed in people.

From our Q&A

Real reader questions about these medications, each personally answered by our pharmacist:

Questions for your pharmacist

  • Does my dose of Codeine or Dexamethasone Ophthalmic 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 (2)

  1. Product Information: Codeine sulfate oral solution, codeine sulfate oral solution. Hikma Pharmaceuticals USA Inc(per FDA), Berkeley Heights, NJ, 2023. DailyMed
  2. Product Information: Codeine sulfate oral tablets, codeine sulfate oral tablets. Hikma Pharmaceuticals USA Inc. (per FDA), Berkeley Heights, NJ, 2023. DailyMed
Was this write-up helpful?

Check another combination

Our instant two-drug interaction checker is almost here.

Coming soon

The instant two-drug checker is on its way.

In the meantime, browse the directory below to look up any drug and see its documented interactions.

Still have questions about this combination?

Every question gets a real answer from a licensed pharmacist — free, and usually within a day.

Ask the pharmacist
This information is for education, not a substitute for professional medical advice. Do not start, stop, or change any medication without talking to your pharmacist or prescriber.