Methadone with Didanosine Interaction Details
Brand Names Associated with Methadone
- Diskets®
- Dolophine®
- Methadone
- Methadose®
- Methadose® Oral Concentrate
- Westadone®
Medical Content Editor Dr. Brian Staiger, PharmD
Last updated
Jan 02, 2024
Interaction Effect
Decreased didanosine efficacy
Interaction Summary
Concomitant administration of didanosine and methadone appear to decrease the serum concentrations of didanosine. Appropriate doses for this combination, with respect to safety and clinical efficacy, have not been established. In opiate-dependent patients, the coadministration of didanosine and methadone may result in decreased area under the concentration-time curve (AUC) and peak drug concentrations (Cmax) for didanosine. If administered in the tablet formulation, a larger dose of didanosine may be required in patients maintained on methadone . If coadministration of methadone and didanosine is warranted, the delayed release, enteric-coated beadlet formulation is preferred .
Severity
Moderate
Onset
Rapid
Evidence
Probable
How To Manage Interaction
If concomitant administration of methadone and didanosine is required, patients should be monitored for decreased didanosine efficacy. If both medications are required, the recommended formulation of didanosine is the enteric-coated beadlets (delayed release-capsules). The pediatric powder for solution formulation is not recommended for use with methadone due to significant decreases in didanosine concentrations .
Mechanism Of Interaction
Decreased didanosine bioavailability
Literature Reports
A) Sixteen patients received chronic maintenance dose of methadone and didanosine 200 mg as a single dose. Steady-state area under the concentration-time curve (AUC) for didanosine decreased 57% and Cmax by 66%. When methadone was administered concomitantly with didanosine 400 mg the steady-state AUC of didanosine was decreased 29% and Cmax by 41% .
B) Treatment with didanosine may be negatively affected if administered in patients maintained on methadone therapy. The effects of methadone on the pharmacokinetics of the tablet formulation of didanosine and stavudine were examined in seventeen patients stabilized on methadone therapy and in ten untreated controls. A 66% reduction (p equals 0.007) in peak didanosine concentration (Cmax) and an approximately 60% reduction in the area under the concentration-time curve (AUC) was observed. The authors of the report hypothesized that methadone slows gastrointestinal motility, decreasing the absorption rate of didanosine. The result is decreased bioavailability since didanosine degradation increases in the gastrointestinal tract, or greater loss due to first-pass metabolism .
Methadone Overview
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Methadone is used to relieve severe pain in people who are expected to need pain medication around the clock for a long time and who cannot be treated with other medications. It also is used to prevent withdrawal symptoms in patients who were addicted to opiate drugs and are enrolled in treatment programs in order to stop taking or continue not taking the drugs. Methadone is in a class of medications called opiate (narcotic) analgesics. Methadone works to treat pain by changing the way the brain and nervous system respond to pain. It works to treat people who were addicted to opiate drugs by producing similar effects and preventing withdrawal symptoms in people who have stopped using these drugs.
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Definitions
Severity Categories
Contraindicated
These drugs, generally, should not be used together simultaneously due to the high risk of severe adverse effects. Combining these medications can lead to dangerous health outcomes and should be strictly avoided unless otherwise instructed by your provider.
Major
This interaction could result in very serious and potentially life-threatening consequences. If you are taking this drug combination, it is very important to be under close medical supervision to minimize severe side effects and ensure your safety. It may be necessary to change a medication or dosage to prevent harm.
Moderate
This interaction has the potential to worsen your medical condition or alter the effectiveness of your treatment. It's important that you are monitored closely and you potentially may need to make adjustments in your treatment plan or drug dosage to maintain optimal health.
Minor
While this interaction is unlikely to cause significant problems, it could intensify side effects or reduce the effectiveness of one or both medications. Monitoring for changes in symptoms and your condition is recommended, and adjustments may be made if needed to manage any increased or more pronounced side effects.
Onset
Rapid: Onset of drug interaction typically occurs within 24 hours of co-administration.
Delayed: Onset of drug interaction typically occurs more than 24 hours after co-administration.
Evidence
Level of documentation of the interaction.
Established: The interaction is documented and substantiated in peer-reviewed medical literature.
Theoretical: This interaction is not fully supported by current medical evidence or well-documented sources, but it is based on known drug mechanisms, drug effects, and other relevant information.
How To Manage The Interaction
Provides a detailed discussion on how patients and clinicians can approach the identified drug interaction as well as offers guidance on what to expect and strategies to potentially mitigate the effects of the interaction. This may include recommendations on adjusting medication dosages, altering the timing of drug administration, or closely monitoring for specific symptoms.
It's important to note that all medical situations are unique, and management approaches should be tailored to individual circumstances. Patients should always consult their healthcare provider for personalized advice and guidance on managing drug interactions effectively.
Mechanism Of Interaction
The theorized or clinically determined reason (i.e., mechanism) why the drug-drug interaction occurs.
Disclaimer: The information provided on this page is for informational purposes only and should not be considered medical advice. Always consult with a qualified healthcare professional regarding your specific circumstances and medical conditions.
Where Does Our Information Come From?
Information for our drug interactions is compiled from several drug compendia, including:
The prescribing information for each drug, as published on DailyMED, is also used.
Individual drug-drug interaction detail pages contain references specific to that interaction. You can click on the reference number within brackets '[]' to see what reference was utilized.
The information posted is fact-checked by HelloPharmacist clinicians and reviewed quarterly.