What should a case manager do if a claimant is on both Codeine and Midazolam?

This is a major interaction. Case managers should immediately flag the combination for prescriber review, request clinical justification, consider an independent medical examination, and document the intervention in the claim file. This combination typically warrants a Reasonable and Necessary determination.

Is the Codeine and Midazolam combination covered under workers compensation?

Coverage depends on the jurisdiction and whether both medications are reasonable and necessary for the compensable injury. In Australia, SIRA and WorkSafe guidelines flag high-risk combinations for review. In the US, state drug formularies may restrict concurrent prescribing. In the UK, NICE guidelines recommend against certain combinations for chronic pain management.

Major Drug Interaction

Can You Take Codeine with Midazolam?

Q: Can you take Codeine with Midazolam?

Codeine and Midazolam should not be taken together due to major interaction severity. Life-threatening respiratory depression, overdose, coma, and death.

A plain-English look at the major interaction between Codeine (Aspen Pharmacare Australia Pty Ltd) and Midazolam (Pfizer Australia Pty Ltd) — what it means, why it happens, and what to talk to your doctor or pharmacist about.

Major severity AllMeds interaction database Updated April 2026

Taking Codeine (Aspen Pharmacare Australia Pty Ltd) with Midazolam (Pfizer Australia Pty Ltd) is a major drug interaction that should be avoided. Life-threatening respiratory depression, overdose, coma, and death. Additive CNS and respiratory depression. Both drug classes suppress breathing through different mechanisms, creating synergistic respiratory depression that can be fatal.

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Key Takeaways

Interaction severity: Major
Risk: Life-threatening respiratory depression, overdose, coma, and death.
Mechanism: Additive CNS and respiratory depression. Both drug classes suppress breathing through different mechanisms, creating synergistic respiratory depression that can be fatal.
Codeine: S8 in Australia, moderate risk
Midazolam: S4 in Australia, moderate risk
Claims action: Flag for immediate prescriber review. Document intervention in claim file.

Codeine vs Midazolam at a Glance

Property	Codeine	Midazolam
Brand names	Aspen Pharmacare Australia Pty Ltd	Pfizer Australia Pty Ltd, Zyamis
Drug class	opioid	benzo
Risk level	moderate	moderate
TGA Schedule (AU)	S8	S4

Why Is This Combination Dangerous?

Additive CNS and respiratory depression. Both drug classes suppress breathing through different mechanisms, creating synergistic respiratory depression that can be fatal.

Clinical risk: Life-threatening respiratory depression, overdose, coma, and death.

Regulatory Guidance by Jurisdiction

Australia TGA / SIRA / WorkSafe

The TGA and Australian Medicines Handbook classify this as a major drug interaction requiring immediate intervention.

All Australian state workers compensation schemes (SIRA NSW, WorkSafe VIC, WorkCover QLD) flag concurrent opioid and benzodiazepine prescribing as high-risk. SIRA best practice guidelines explicitly recommend avoiding this combination except in exceptional circumstances with specialist oversight.

United Kingdom NICE / MHRA / FPM

NICE NG193 (Chronic Pain) recommends against initiating opioids for chronic primary pain. The Faculty of Pain Medicine (FPM) Opioids Aware guidelines strongly advise against concurrent opioid and benzodiazepine prescribing. For personal injury claims in the UK, this combination should be flagged for specialist review. Costs for medication review may be recoverable as a disbursement.

United States FDA / CDC / State WC

The FDA requires a Boxed Warning on all opioid and benzodiazepine products about the risks of concurrent use. The CDC Clinical Practice Guideline (2022) recommends clinicians avoid prescribing opioids and benzodiazepines concurrently whenever possible. Most state workers compensation drug formularies flag or restrict this combination.

What Claims Professionals Should Do

Flag immediately as a high-risk prescribing pattern in the claim file
Request urgent prescriber review with documented clinical justification for the combination
Consider an independent medical examination if the prescriber cannot provide adequate justification
Assess work capacity impact as the combination significantly increases sedation and impairment risk
Document all interventions for audit trail and compliance purposes
Check Reasonable and Necessary status for both medications against the compensable injury

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Related Resources

Medical Disclaimer: This content is for informational purposes for claims professionals and care workers. It is not medical advice. Always consult a qualified healthcare professional for clinical decisions. Drug information is sourced from TGA, FDA, MHRA, PBS, NICE, and CDC databases and may not reflect the latest updates. AllMeds does not replace clinical judgement.