Didanosine and Indinavir: Interaction Details
AI-assisted, pharmacist-reviewed · Source data updated Aug 8, 2026 · Sources: FDA labeling, DDInter 2.0, cited literature
Indinavir
No brand names on recordDidanosine
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
Decreased bioavailability and therapeutic efficacy of indinavir
Interaction Deep Dive
Didanosine pediatric powder for oral solution or chewable/buffered tablets and indinavir should not be administered simultaneously due to different requirements for optimal absorption. Didanosine pediatric powder for oral solution and chewable/buffered tablets contain antacids that can raise the stomach pH. Indinavir is thought to be more completely absorbed under the normal acidic conditions of the stomach. . Didanosine pediatric powder for oral solution and chewable/buffered tablets should be administered at least one hour after indinavir24. No specific administration adjustments are recommended for the coprescription of didanosine delayed release capsules/enteric coated beadlets and indinavir.1.
Why it happens (mechanism)
Decreased absorption of indinavir
Literature reports
1 report — tap to read
a) Indinavir 800 mg as a single dose administered simultaneously with 200 mg of didanosine pediatric powder for oral solution in 16 healthy volunteers resulted in a decrease in indinavir AUC and Cmax by 84% and 82%, respectively. There was no significant change in didanosine AUC or Cmax. When the same dose of indinavir was administered one hour before didanosine, the indinavir AUC and Cmax decreased by 11% and 4%, respectively, while AUC and Cmax of didanosine decreased by 17% and 13%, respectively 2. When indinavir 800 mg as a single dose was administered simultaneously with 400 mg of didanosine delayed release capsules/enteric coated beadlets in 23 healthy volunteers, indinavir AUC and Cmax were not significantly changed 1.
Common questions
Can I take Didanosine and Indinavir together?
Decreased bioavailability and therapeutic efficacy of indinavir Always confirm with your pharmacist or prescriber before making any change.
How serious is the Didanosine and Indinavir interaction?
It is rated moderate. Can be significant — usually manageable with monitoring.
How quickly could this interaction happen?
The documented onset is "rapid". Effects can appear quickly, often within about 24 hours of combining the drugs.
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 Didanosine or Indinavir 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 anything you'd monitor while I'm on both?
References (4)
- Product Information: VIDEX EC(R) delayed release oral capsules, enteric coated beadlets, didanosine delayed release oral capsules, enteric coated beadlets. Bristol-Myers Squibb Company, Princeton, NJ, 2009.
- Product Information: VIDEX(R) pediatric powder for oral solution, didanosine pediatric powder for oral solution. Bristol-Myers Squibb Company, Princeton, NJ, 2009.
- Product Information: CRIXIVAN(R) oral capsules, indinavir sulfate oral capsules. Merck & Co, Inc, Whitehouse Station, NJ, 2008. DailyMed
- Product Information: Crixivan(R), indinavir sulfate. Merck & Co. Inc. Whitehouse Station, NJ, 2004. DailyMed
Keep reading about Indinavir
Keep reading about Didanosine
These medications also interact with supplements
Prescription drugs aren't the whole picture — herbal and dietary supplements can interact with them too. From the evidence-graded Natural Medicines database:
major · moderate · minor — check everything you take with our drug–supplement interaction checker.
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